PART II

MARINE INVERTEBRATES

I PORIFERA (SPONGES) 99

II C[OE]LENTERATA (POLYPS) 111

III WORMS 159

(PLATYHELMINTHES, NEMATHELMINTHES, ANNULATA)

IV MOLLUSCOIDA 187

V ECHINODERMATA 199

VI ARTHROPODA 237

VII MOLLUSCA 299

VIII CHORDATA 471

INDEX 479

INTRODUCTION

In vain through every changeful year

Did nature lead him as before;

A primrose by a river's brim,

A yellow primrose was to him,

And it was nothing more.

At noon, when by the forest's edge

He lay beneath the branches high,

The soft blue sky did never melt

Into his heart; he never felt

The witchery of the soft blue sky.

WORDSWORTH.

To him who in the love of Nature holds

Communion with her visible forms, she speaks

A various language.

BRYANT.

INTRODUCTION

I

SIGNS ON THE BEACH

The sea-shore, with its stretches of sandy beach and rocks, seems,

at first sight, nothing but a barren and uninteresting waste, merely

the natural barrier of the ocean. But to the observant eye these

apparently desolate reaches are not only teeming with life; they are

also replete with suggestions of the past. They are the pages of a

history full of fascination for one who has learned to read it.

In this history even the grains of sand have a part. Though so humble

now, they once formed the rocky barriers of the shore. They stood

as do the rocks of to-day, defiant and seemingly everlasting, but

the fury of the sea, which knows no invincible adversary, has laid

them low. Every coast-line shows the destructive effects of the sea,

for the bays and coves, the caves at the bases of the cliffs, the

buttresses, stocks, needles, and skerries, are the work of the waves.

And this work is constantly going on.

Even a blind man could not stand long upon a shingly beach without

knowing that the sea was busily at work. Every wave that rolls

in from the open ocean hurls the pebbles up the slope of the

beach, and then as soon as the wave has broken and the water has

dispersed, these pebbles come rattling down with the currents that

sweep back to the sea. The clatter of the beach thus tells us

plainly that as the stones are being dragged up and down they are

constantly knocked against each other; and it is evident that by

such rough usage all [pg002] angular fragments of rock will soon

have their corners rounded off and become rubbed into the form of

pebbles. As these pebbles are rolled to and fro upon the beach they

get worn smaller and smaller, until at length they are reduced

to the state of sand. Although this sand is at first coarse, it

gradually becomes finer and finer as surely as though it were

ground in a mill; and ultimately it is carried out to sea as fine

sediment and laid down upon the ocean floor.[1]

[Footnote 1: Huxley.]

The story of the sands is not only one of the conflict of the sea

and rocks; it is also a story of the winds. It is the winds that

have rescued them from the waves and driven them about, sifting

and assorting them, arranging them in graceful forms, and often

heaping them up into dunes which, until fastened by vegetation, are

themselves ever moved onward by the same force, sometimes burying

fertile lands, trees, and even houses in their march. The sands,

moreover, are in turn themselves destructive agents, to whose power

the many fragments which strew the beach and dunes bear ample

witness. The knotty sticks so commonly seen on the beach are often

the hearts of oak- or cedar-trees from which the tiny crystals of

sand have slowly cut away their less solid outer growth. Everything,

in fact, upon the sands is "beach-worn," even to the window-glass of

life-saving stations, which is frequently so ground that it loses its

transparency in a single storm.

The beach is also a vast sarcophagus holding myriads of the dead.

"If ghosts be ever laid, here lie ghosts of creatures innumerable,

vexing the mind in the attempt to conceive them." And there are

certain sands which may be said to sing their requiem, the so-called

musical sands, like the "Singing Beach" at Manchester-by-the-Sea,

which emit sounds when struck or otherwise disturbed. On some

beaches these sounds resemble rumbling, on others hooting; sometimes

they are bell-like and even rhythmical. The cause of this sonorous

character is not definitely known, but it is possibly due to films

of compressed gases which separate each grain as with a cushion, and

the breaking of which [pg003] causes, in the aggregate, considerable

vibrations. Such sands are not uncommon, having been recorded in

many places, and they exist probably in many others where they have

escaped observation. They may be looked for above the water-line,

where the sand is dry and clean.

We have to do, however, in this volume, not with the history of the

past, nor with the action of physical forces, but with the life of

the present, and to find this, in its abundance, one must go down

near the margin of the water, where the sands are wet. There is no

solitude here; the place is teeming with living things. As each wave

retreats, little bubbles of air are plentiful in its wake. Underneath

the sand, where each bubble rose, lives some creature, usually a

mollusk, perhaps the razor-shell /Solen ensis/. By the jet of water

which spurts out of the sand, the common clam /Mya arenaria/ reveals

the secret of its abiding-place. A curious groove or furrow here and

there leads to a spot where /Polynices heros/ has gone below; and the

many shells scattered about, pierced with circular holes, tell how

/Polynices/ and /Nassa/ made their breakfast and their dinner. Only

the lifting of a shovelful of sand at the water's edge is needed to

disclose the populous community of mollusks, worms, and crustaceans

living at our feet, just out of sight.

Even the tracks and traces of these little beings are full of

information. What may be read in the track of a bird on the sand is

thus described by a noted ornithologist:

Here are foot-notes again, this time of real steps from real

feet. . . . The imprints are in two parallel lines, an inch or so

apart; each impression is two or three inches in advance of the

next one behind; none of them are in pairs, but each one of one

line is opposite the middle of the interval between two of the

other line; they are steps as regular as a man's, only so small.

Each mark is fan-shaped; it consists of three little lines less

than an inch long, spreading apart at one extremity, joined at

the other. At the joined end, and also just in front of it, a

flat depression of the sand is barely visible. Now following the

track, we see it run straight a yard or [pg004] more, then twist

into a confused ball, then shoot out straight again, then stop,

with a pair of the footprints opposite each other, different from

the other end of the track, that began as two or three little

indistinct pits or scratches, not forming perfect impressions of a

foot. Where the track twisted there are several little round holes

in the sand. The whole track commenced and finished upon the open

sand. The creature that made it could not, then, have come out

of either the sand or the water; it must have come down from the

air--a two-legged flying thing, a bird. To determine this, and,

next, what kind of bird it was, every one of the trivial points of

the description just given must be taken into account. It is a bit

of autobiography, the story of an invitation to dine, acceptance,

a repast, an alarm at the table, a hasty retreat. A bird came on

wing, lowering till the tips of its toes just touched the sand,

gliding half on wing, half afoot, until the impetus of flight was

exhausted; then folding its wings, but not pausing, for already a

quick eye spied something inviting; a hasty pecking and probing to

this side and that, where we found the lines entangled; a short run

after more food; then a suspicious object attracted its attention;

it stood stock-still (just where the marks were in a pair), till,

thoroughly alarmed, it sprang on wing and was off.[2]

[Footnote 2: Elliott Coues.]

Following the key further, he draws more conclusions. The tracks are

not in pairs, so the bird does not belong to the perchers; therefore

it must be a wader or a swimmer. There are no web-marks to indicate

the latter; hence it is a three-toed walking or wading bird. It had

flat, long, narrow, and pointed wings because it came gliding swiftly

and low, and scraped the sand before its wings were closed. This

is shown by the few scratches before the prints became perfect. A

certain class of birds thus arrests the impetus of flight. It had a

long feeling-bill, as shown by the little holes in the sands where

the marks became entangled; and so on. These combined characteristics

belong to one class of birds and to no other; so he knows as

definitely as [pg005] though he had seen the bird that a sandpiper

alighted here for a brief period, for here is his signature.

It is plain that tracks in the sand mean as much to the naturalist as

do tracks in the snow to the hunter, and trails on the land to the

Indian who follows his course by signs not seen by an untrained eye.

The tide effaces much that is written by foot and wing, but sometimes

such signs are preserved and become veritable "footprints on the

sands of time." In the Museum of Natural History in New York is

a fossil slab, taken from the Triassic sandstone, showing the

footprints of a dinosaurian reptile now extinct, which, in that long

ago, walked across a beach--an event unimportant enough in itself,

but more marvelous than any tale of imagination when recorded for

future ages. From such tracks, together with fragments of skeletons,

the dinosaur has been made to live again, and its form and structure

have been as clearly defined as those of the little sandpiper of Dr.

Coues.

[pg006]

II

COLLECTING

It has been said that everything on the land has its counterpart

in the sea. But all land animals are separate and independent

individuals, while many of those of the sea are united into organic

associations comprising millions of individuals inseparably connected

and many of them interdependent, such as corals, hydroids, etc. These

curious communities can be compared only to the vegetation of the

land, which many of them resemble in outer form. Other stationary

animals, such as oysters and barnacles, which also depend upon

floating organisms for their food, have no parallel on the land.

The water is crowded with creatures which prey upon one another,

and all are interestingly adapted to their mode of life. Shore

species are exceedingly abundant, and the struggle for life is there

carried on with unceasing strife. In the endeavor to escape pursuers

while they themselves pursue, these animals have various devices of

armature and weapons of defense; they have keen vision, rapid motion,

and are full of arts and wiles. One of the first resources for safety

in this conflict is that of concealment. This is effected not only

by actual hiding, but very generally by mimicry in simulating the

color of their surroundings, and often by assuming other forms. Thus,

for instance, the sea-anemone when expanded looks like a flower and

is full of color, but when it contracts becomes so inconspicuous as

to be with difficulty distinguished from the rock to which it is

attached. Anemones also have stinging threads (nematophores), which

they dart out for further defense. [pg007]

The study of biology has great fascination, and the subject seldom

fails to awaken interest as soon as the habit of observation is

formed. Jellyfishes, hardly more dense than the water and almost as

limpid, swimming about with graceful motion, often illuminating the

water at night with their phosphorescence, showing sensitiveness,

volition, and order in their lives, cannot fail to excite wonder

in even the most careless observer. Not less interesting are the

thousands of other animals which crowd the shores, lying just beneath

the surface of the sand, filling crevices in the rocks, hiding under

every projection, or boldly--perhaps timidly, who shall say?--lying

in full view, yet so inconspicuous that they are easily passed by

unnoticed.

To find these creatures, to study their habits and organization, to

consider the wonderful order of nature, leads through delightful

paths into the realms of science. But even without scientific study

the simple observation of the curious objects which lie at one's feet

as one walks along the beach is a delightful pastime.

The features which separate the classes and the orders of both the

plant and the animal life are so distinctive that it requires but

very superficial observation to know them. It is easy to discriminate

between mollusks, echinoderms, and polyps, and to recognize the

relationship between univalves and bivalves, sea-urchins and

starfishes, sea-anemones and corals. The equally plain distinctions

between the branched, unbranched, tubular, and plate-like green algæ

make them as easy to separate.

The pleasure of a walk through field or forest is enhanced by knowing

something of the trees and flowers, and in the same way a visit to

the sea-shore becomes doubly interesting when one has some knowledge,

even though it be a very superficial one, of the organisms which

inhabit the shore.

ROCKY SHORES

Rocky shores furnish an abundance and great variety of objects to the

collector. The seaweeds here find places of attachment, and the lee

and crevices of the rocks afford shelter to many animals which could

not live in more open and exposed places. The [pg008] rock pools

harbor species whose habitat is below low-water mark and which could

not otherwise bear the alternation of the tides.

The first objects on the rocky beach to attract attention are the

barnacles and rockweeds. They are conspicuous in their profusion,

the former incrusting the rocks with their white shells, and the

latter forming large beds of vegetation; yet both are likely to be

passed by with indifference because of their plentifulness. They are,

however, not only interesting in themselves, but associated with

them are many organisms which are easily overlooked. The littoral

zone is so crowded with life that there is a constant struggle for

existence,--even for standing-room, it may be said,--and no class

of animals has undisputed possession of any place. Therefore the

collector should carefully search any object he gathers for other

organisms which may be upon it, under it, or even in it, such as

parasites, commensals, and the organisms which hide under it or

attach themselves to it for support. Let the rockweed (/Fucus/) be

carefully examined. Among the things likely to be found attached to

its fronds are periwinkles (/Littorina litorea/), which simulate

the plant in color, some shells being striped for closer mimicry.

Sertularian hydroids also are there, zigzagging over the fronds or

forming tufts of delicate horny branches upon them. Small jelly-like

masses at the broad divisions of the fronds may be compound

ascidians. Calcareous spots here and there may be polyzoans of

exquisite form, while spread in incrusting sheets over considerable

spaces are other species of /Polyzoa/. Tiny flat shelly spirals

are the worm-cases of /Spirorbis/. A pocket-lens is essential to

enable one to appreciate the beauty of these minute forms. Under the

rockweeds are many kinds of crustaceans; perhaps there will also be

patches of the pink urn-like egg-capsules of /Purpura/ at the base of

the fucus.

Various kinds of seaweed abound in the more sheltered parts of the

rocks, and among them will be found amphipods and isopods, many of

which are of species different from those of the sandy beaches. Here,

too, is the little /Caprella/, imitating the seaweed in form, and

swaying its lengthened body, which is attached to the plant only by

its hind legs. On the seaweeds, as well as in the tide-pool, may be

found beautiful hydroids, and on [pg009] them the curious little

sea-spiders (/Pycnogonidæ/), animals which seem to be all legs.

Mollusks, and other classes as well, differ in different latitudes.

On the rocks of the Northern shores /Littorina/ and /Purpura/ shells

are very abundant, the latter in various colors and beautifully

striped. Limpets are also plentiful, but are not as conspicuous,

since they have flat, disk-shaped shells. When their capture is

attempted, they must be taken unawares and pushed quickly aside,

else they take such a firm hold of the rock that it is difficult

to dislodge them. Near low-water mark under ledges will perhaps be

found chitons, which are easily recognized by their oval, jointed

shells. On the California coast in like localities will be found

the beautiful /Haliotis/, /Acmæa/, and chitons. Every stone that

is lifted will disclose numbers of little amphipods (/Gammarus/),

which will scuttle away on their sides to other shelter; worms will

suddenly disappear into the mud, and perhaps a crab, here and there,

having no alternative, will make a stand and fight for his liberty.

Flat against the stone and not easily perceived may be a chiton, a

planarian worm, or a nudibranch. And just below the water's edge are

sea-urchins and starfishes, which grow in numbers as the eye becomes

accustomed to the search.

The rock pools are natural aquaria, more interesting by far than any

prepared by man. The possibilities of these little sea-gardens are

beyond enumeration. The longer one studies them the more one finds.

In them all classes of seaweeds and marine invertebrates may be found

and their habits watched. The great beauty of these pools gives them

an esthetic charm apart from the scientific interest they excite.

Perhaps one may find here a sponge, and removing it to a shallow

vessel of sea-water can watch the currents of water it creates.

Several sponges of the same species placed in contact will at the

end of two days be closely united. If the sponges are of different

species they will not coalesce.

In the clefts and crannies of the rocks are various fine seaweeds,

often of the red varieties, sea-anemones, hydroids, polyzoans,

crustaceans, mollusks, and ascidians. Crabs will be snugly [pg010]

ensconced under projecting surfaces. Most species are more plentiful

at the lowest-water mark, and many are found only at this point and

below.

SANDY SHORES

On sandy shores the greater part of the inhabitants live under the

surface. Many give evidence of their presence by the open mouths of

their burrows, and some distinctly point out these places by piles

of sand or mud in coils at the opening. Some tubicolous worms have

their tubes projecting above the surface. The tubes of /Diopatra/

are hung with bits of shells, seaweeds, and other foreign matter.

Some mollusks announce themselves by spurting jets of water or

sending bubbles of air from the sand. The majority of the underground

species, however, give no sign of their presence on the surface,

and must be found by digging. Many of them go deep into the sand,

and in searching for worms the digger must be quick- and expert,

or he will lose entirely or cut in two many of the most beautiful

ones, which retreat quickly and to the extremity of their holes at

the least alarm. One can be a rambler on the sandy beach for a long

time without being aware of the many beautiful objects which inhabit

the subsurface of the sand. The curious crab /Hippa/ will disappear

so quickly into the sand that one is hardly sure he has really seen

it. The vast number of worms will surprise any one who searches for

them by their variety, their beautiful color, and their interesting

shapes. Here again a glass is requisite to appreciate the delicacy

and beauty of their locomotive organs, their branchiæ, and so on. The

most common of the gasteropod mollusks on sandy shores are /Nassa

obsoleta/, /Nassa trivittata/, and /Polynices (Lunatia) heros/. The

last are detected by the little mounds of sand which they push before

them as they plow their way just below the surface. On more southern

beaches, /Fulgur/, /Strombus/, and /Pyrula/ are the common varieties.

/Olivella/, /Oliva/, and /Donax/, also inhabitants of sandy beaches,

will quickly disappear when uncovered by the waves, being rapid

burrowers. Most of the many dead shells on the beach will be found

to be pierced with a round hole, which is [pg011] drilled by the

file-like tongue, or lingual ribbon, of /Polynices/, /Urosalpinx/,

or /Nassa/, which thus reach the animal within and suck out its

substance. Another similar species is /Polynices/ (/Neverita/)

/duplicata/, which extends to the Gulf of Mexico, while /P. heros/

is not commonly found below Hatteras. Crustaceans are abundant on

the sandy beach over its whole breadth. Some of the sand-crabs live

above tide-mark. Among these is the fleet-footed /Ocypoda/, which is

interesting to watch. Often they go in numbers to the water's edge

and throw up mounds, behind which they crouch like cats, watching

for whatever prey the tide may bring up. When unable to outrun a

pursuer they rush into the surf and remain there until the danger is

past. The wet sand is often thickly perforated with the burrows of

the sandhoppers (/Orchestia/). These often rise about the feet as do

grasshoppers in the fields.

[Illustration: PLATE I. Egg-capsules of Purpura lapillus. Egg-case of

Polynices heros. Egg-capsules of Buccinum undatum. Egg-case of the

skate. Fulgur canaliculata (whelk) and egg-cases.]

/Hippa talpoida/ is a remarkable crab, somewhat resembling an egg.

It is not likely to be seen unless searched for by digging at the

water's edge. It burrows so rapidly that one must be quick to catch

it after it is exposed by the shovel. In some places the tests of

"sand-dollars" are common. The living animal may be found buried just

below the surface at extreme low-water mark.

The sea-wrack drifted in lines along the shore will repay careful

examination, for here will be found many things belonging to other

shores and deep water. It is often alive with sandhoppers, which

hop away while one searches for less common things. Often the most

delicate seaweeds, numerous small shells, worms, polyzoans, etc.,

will be found there.

The surface of the sand-beach is strewn with remains of many species,

usually beach-worn, but interesting nevertheless as examples of

species one would like to find in better condition, but good

specimens of which elude ordinary search or are unobtainable except

by dredging.

Egg-cases form another class of objects which are often gathered with

no idea of their identity. Of these the most common are the long

strings of saucer-like capsules which contain the eggs of the mollusk

/Fulgur/, those having square edges being [pg012] the egg-cases of

/F. carica/, and those having sharp edges those of /F. canaliculata/.

Collar-like sandy rings contain the eggs of /Polynices/ (/Lunatia/),

which are cemented together in this shape. The boys of Cape Cod

call them "tommy-cod houses." Cylindrical piles of little capsules,

sometimes called "ears of corn," hold the eggs of /Chrysodomus/. The

irregular masses of small hemispherical capsules are those of the

common whelk (/Buccinum/). The so-called "Devil's pocket-books" are

the egg-cases of the skate.

MUDDY SHORES

On muddy shores the eel-grass (/Zostera marina/) grows abundantly,

giving an appearance of submerged meadows. It is one of the very

few flowering plants which live in salt water. In summer its little

green blossoms may be seen in grooves on the leaf-like blades. Many

animals live on and among eel-grass. Found upon it is the delicate

gasteropod mollusk /Lacuna vincta/, and its eggs in little rings; the

iridescent /Margarita helicina/, and /Nassa/, with its bright-yellow

eggs in small gelatinous masses; also little worms (/Spirorbis/) in

tiny flat spiral shells, compound ascidians in jelly-like masses,

clusters of shelly or horny polyzoans, isopods, planarian worms, and

so on. Scallops (/Pecten/) will be found at the base of the plants,

and the common prawns are very numerous, swimming freely about. Mud

flats and shores are the homes of many mollusks, especially of /Nassa

obsoleta/,--which is the most abundant shell of any considerable size

from Cape Cod to the Gulf of Mexico,--and of vast numbers of the tiny

/Littorinella minuta/, which serve as food for fishes and aquatic

birds. Clams and worms of all varieties are also abundant.

There are many varieties of mud-crabs, of which the most common

are the "fiddlers," which honeycomb the banks and the surface of

salt-marshes with their burrows. The common edible crab /Callinectes

hastatus/ is plentiful in bays and estuaries. The sluggish

spider-crabs hide beneath the surface of the mud and in decaying

weeds and eel-grass. Hermit-crabs are plentiful here as well as

elsewhere. /Panopeus/ is a sluggish crab found in shallow water and

in all sorts of hiding-places along the shore. It [pg013] may often

be found in dead shells, and, in the South, in holes in the banks.

This genus is represented by a number of species, some of which are

quite pretty.

WHARVES AND BRIDGES

On the piles of wharves and bridges may often be found beautiful

tubularian hydroids in large tufts just below low-water mark,

branched hydroids looking like little shrubs, polyzoans,

sea-anemones, mollusks, and ascidians. The species peculiar to these

localities are the boring mollusk /Teredo navalis/, or ship-worm, the

boring isopod /Limnoria lignorum/, and the boring amphipod /Chelura

terebrans/, all of which penetrate the wood and are most destructive.

The animals and plants of tropical beaches and coral reefs are

so various and abundant, so curious and beautiful, as to make

a description or even an enumeration of them in a brief space

difficult. The collector is bewildered and excited when he first

views the profusion of the wonderful forms there found.

It is not generally known that a fine species of "stony coral"

is common from Cape Cod southward, growing in clear water as an

incrustation on rocks, and developing little spires as it advances in

age. This species, the /Astrangia danaë/, is especially interesting,

since it will live in a dish of clear sea-water, and the polyps will

expand, showing a very close relationship to the sea-anemone. With

care in changing the water this coral will live for days, and may be

examined in its expanded condition with a lens of moderate power.

The most favorable time for collecting on any beach is at the lowest

tide, many objects being then uncovered which do not appear higher up

on the beach. At the spring-tides, which occur twice a month, at the

period of the new and that of the full moon, the ebb is especially

low, and affords an opportunity to search for forms whose habitat is

below ordinary low-water mark. During storms deep-water forms are

often torn from their beds and cast upon the beach. Shore-collecting

at these times is often very interesting. [pg014]

EQUIPMENT FOR COLLECTING INVERTEBRATES

The equipment for collecting upon sandy beaches is a shovel, a sieve,

and a net. Numerous trials should be made with the shovel from about

half-tide mark to as deep as one cares to wade, and the sand raised

should be carefully searched for shells, crustaceans, and worms.

By washing out the sand in the sieve the smallest specimens, which

might otherwise escape notice, may be secured. On a rocky beach a

strong knife and a net are sufficient. It is well to have a number

of homeopathic vials for small specimens, which will be injured

by contact with larger forms, and jars for holding the general

collection.

PRESERVING INVERTEBRATES

To preserve specimens, they should first be placed in a weak solution

of alcohol, the strength of which should be increased gradually until

the animal is entirely free from water and is hardened throughout.

If the alcohol becomes colored and sediment falls to the bottom

of the jar, the animal is degenerating, and the alcohol should be

changed. Specimens for transportation can be packed by wrapping each

one in a bit of cheese-cloth and then placing them together in a

large receptacle. Care should be taken to keep the fragile specimens

separate. Sand-dollars possess a pigment which discolors and soon

vitiates alcohol, and consequently these should be separated from

the other forms and placed where the alcohol may be changed from

time to time as appears necessary. The homeopathic vials containing

small specimens may be put into the can without injury to the other

specimens. Special cans of various sizes, with handles and screw

covers, are made for naturalists. One of these cans is a convenient

receptacle for carrying the alcohol to the station and for receiving

the collection for transportation. Careful notes should be made on

the spot of the conditions under which the species are found. One is

likely to forget details if this is delayed until one reaches home.

Labels should be used, giving name when known, or a number when the

name is not known, [pg015] corresponding with the note-book. Names

written with lead-pencil on a slip of paper will not be defaced by or

injure the alcohol. Collections when arranged permanently should be

placed in glass jars, the species being kept separate.

COLLECTING AND PRESERVING SEAWEEDS

To collect seaweeds one must search for them on rocks, in tide-pools,

in the sea-wrack upon the beach, on piles of wharves, on eel-grass,

and on the surface of incoming waves. It is well to follow the

receding tide and take advantage of its lowest ebb (especially of

that of the spring-tides, as mentioned above) to search the extreme

limit of the beach in the short time it is exposed. Many of the red

seaweeds are found there.

The equipment for collecting consists of a basket, two small tin

pails, one small enough to be carried within the other, a staff

with an iron edge at one end and a small net at the other, and a

pocket-lens. Rockweeds (/Fucus/) or other coarse gelatinous seaweeds

should be put into the basket. The pails, half filled with sea-water,

will receive the other specimens, fine and delicate algæ being put

into the smaller pail. It is well to have a second small receptacle

for /Callithamnion/ and /Griffithsia/, if one can be further

burdened. /Desmarestia/ should be kept apart, if possible, since it

discolors and decomposes other algæ; it should also have the earliest

attention when the time comes for mounting, and salt water should

be used for floating it upon the mount, otherwise the beauty of the

specimen will be impaired.

Besides its use as a support, the staff is needed to dislodge

specimens from the rocks, and the net to secure those that are

floating just out of reach. When possible, it is desirable to secure

the whole plant, including the holdfast, and to gather several

plants of the same species, since they vary with age and other

conditions, and it is also well to have duplicates for exchange. It

is particularly desirable to obtain plants which are in fruit. Each

specimen as it is taken should be rinsed in the sea-water to free it

from sand.

Collections should be mounted as soon as convenient, and [pg016]

especial care in this respect should be taken with red algæ, as they

decompose quickly. The requisites for mounting are blotters, pieces

of muslin, two or more smooth boards, weights, a basin, and several

shallow dishes containing water. Fresh water has a strong action on

the color and substance of seaweeds, and specimens should not be left

in it for any length of time.

Lift a specimen from the general collection, and in a basin of deep

water carefully wash off all superfluous matter; then place it in

shallow water and spread it out, trimming it judiciously, so that

when mounted it will not be too thick and the characteristics be

hidden. Specimens are more interesting and their species more easily

determined when laid out rather thin, showing their branching and

fruit. After the specimen is thus prepared, place it in a second

shallow dish of water. It should now be perfectly clean. Float it out

into the desired position, spreading it well, letting some parts show

the details of the branching, and other parts the general natural

effect of the mass. Run under it a rather heavy sheet of white paper,

and lift it carefully from the water. If raised from the center,

it is easier to let the water subside evenly and gradually without

disarranging the parts. Some collectors find it better to float the

specimen in water deep enough to allow the left hand to be placed

under the sheet to raise it. Lay the sheet on a plate, and with a

needle or forceps rearrange any of the delicate parts which have

fallen together. A few drops of water placed on any portion will

usually be sufficient to enable one to separate the branchlets or

ultimate ramifications. A magnifying-glass will be useful in this

work.

Cover a blotter with mounted specimens, spread over them a piece

of cotton cloth, and on this place another blotter, upon which lay

more mounted specimens and a cloth. Proceed in this way until all

the specimens are used. Lay the pile of blotters between boards, and

on them place the weights. The weights should not be very heavy.

Judgment must be used in assorting the specimens, those that are fine

being placed together. Those that are coarse and likely to indent

the blotters should be placed between separate boards. In this way a

flat surface and an even pressure will be obtained. The blotters and

cloths should be [pg017] changed twice each of the first two days,

then the cloths should be removed and the specimens left in press for

a week, the blotters being changed daily. Be sure that the specimens

are perfectly dry before placing them in the herbarium. Label each

specimen with the name and the date and place of collection.

There are some seaweeds which cannot be treated in the above manner.

/Fucus/ if placed in fresh water soon becomes slimy. It is so full of

gelatine that it soon destroys blotters; therefore it is well to hang

it up for several hours and then place it between newspapers, which

should be frequently changed, and as the plant becomes pliable it

should be arranged in proper position.

Those specimens which do not adhere to paper in drying should be

secured with gum. When it is impossible to mount specimens at the

time they are collected, they can be preserved by drying; afterward

they can be soaked and mounted in the usual manner. To dry the

plants, lay them separately upon boards without pressing out the

sea-water, and leave them in an airy, shaded place until thoroughly

dry; then pack them loosely into boxes and label, giving date and

locality. Blotters or driers can be obtained at botanical-supply

stores at thirty-five cents per quire.

HOW TO ARRANGE A HERBARIUM

The standard herbarium-paper is sixteen by eleven and a half

inches. The sheets are single, white, smooth, and quite heavy.

These, together with folded sheets of yellow manila paper, called

genus-covers, are the only requisites. It is desirable to have also

a case of shelves protected by glass doors. The shelves should be

twelve by eighteen inches, and four to six inches apart. They are

more convenient when made to slide like drawers.

The different species of one genus are gummed on one or more of the

white sheets and placed within the folded manila paper, which serves

as a cover. Each specimen should be signed with its name, place, and

date of collection, thus:

/C. rubrum./ Bar Harbor. Aug. 12, 1899,

the generic name being indicated by its initial capital letter and

the specific name written in full. To this are often added the

[pg018] name of the collector and some interesting comment. On the

lower left-hand corner of the genus-cover is written the generic name

in full and the species of that genus which the cover contains, thus:

/Ceramium/ /C. rubrum/

/C. strictum/

/C. diaphanum/

The genera of an order are then placed within a cover and labeled

in the same way, the legend then having the name of the order on

the left and the genera on the right of the bracket, [TN: see

Transcriber's Note.] thus:

/Rhodymeniaceæ/, suborder /Ceramieæ/

/Callithamnion/

/Griffithsia/

/Ceramium/

When the order is a large one the genera are distributed through as

many covers as may be necessary. The covers are then arranged on

shelves in the regular order of their classification, and each shelf

is labeled with the order it contains. Herbarium-sheets cost at

retail one dollar per hundred. Genus-covers cost at retail one dollar

and eighty cents per hundred. [pg019]

III

CLASSIFICATION

The first great biological division is into kingdoms, namely, the

animal kingdom and the vegetable kingdom. Then by classification the

vast number of existing animals and plants are grouped so as to give

each individual a definite place. By this system a beautiful order

is established, which enables the student to find any particular

animal or plant he may wish to study, and also to know its general

characteristics from the name of the group to which it belongs.

In broad generalization, objects of wide dissimilarity are recognized

as belonging to the same kingdom, as do trees and grasses, or as

do birds and fishes. Certain trees or grasses and certain birds or

fishes have such points of resemblance that they plainly show that

they belong to subdivisions. The most untutored people recognize

these distinctions, but the naturalist goes further and finds points

of distinction which the casual observer overlooks.

The animal kingdom has a varying number of divisions, called

/branches/, /subkingdoms/, or /phyla/. Some late authors have

admitted twelve divisions, and have given them the name /phyla/. Each

phylum is composed of a group of animals with a plan of structure

which is common to themselves, but differs from that of the animals

of all other phyla.

The higher animals begin with the twelfth phylum, namely, the

/Chordata/, or vertebrates. These animals have a spinal column, or

series of vertebræ, while the lower animals, or invertebrates are

without a spinal column, and depend for stability [pg020] upon

muscles or coriaceous or calcareous coverings. The vertebrates

are first represented in the fish-like forms. Bilateral symmetry,

however, or the uniform arrangement of parts on each side of

a central axis, exists in several groups which are below the

vertebrates, the first pronounced example being found in worms.

Groups lower than worms have their organs arranged around a central

axis or radiating from it, and were once all classed as /radiates/.

An animal is classified in accordance with its morphology, anatomy,

histology, and embryology. Morphology determines its general shape,

the position of its limbs, eyes, and mouth, and the covering of

its body; anatomy, the arrangement of its internal organs, such as

the position of its heart, lungs, stomach, etc.; histology, the

character of the tissues of the body; and embryology, the method of

the development of the animal from the embryo to maturity. It is only

after these exact discriminations have been made that the groups are

arranged. Owing to the greater accuracy resulting from histology and

embryology (methods which have been employed only in later years),

many changes in classification have been made, and as science

advances will continue to be made.

The primary groups are based on broad general characteristics,

but their divisions and subdivisions are determined by closer

distinctions. Animals having shells differ from those having a

cartilaginous or those having a crustaceous covering, and are placed

in different groups. Yet mollusks having a single or a double shell,

having spiral or flat forms, living on land, in fresh water, or in

the sea, while differing from one another, are all of one group.

Lobsters and crabs, although both have crustaceous coverings, are

very unlike; and again, there are many species of both lobsters and

crabs.

To group individuals, noting resemblances as well as differences,

a system of classification has been arranged with the following

divisions:

Kingdom, Phylum, Class, Order, Family (or Suborder), Genus, Species.

[pg021]

IV

ANIMAL LIFE IN ITS LOWEST FORMS

The biological division, or discrimination, between animal and

vegetable life, is based on the manner of assimilating food. Plants

feed upon mineral substances, or, in other words, assimilate

inorganic matter, while animal life requires for its support

vegetable or some other organic matter.

Animal as well as vegetable life in its lowest forms begins with

one-celled organisms, which are called respectively /Protozoa/ (first

animals) and /Protophyta/ (first plants). Both of these divisions

are composed mostly of microscopic objects, and, together with other

minute forms of life of the marine species, constitute a great part

of the /plankton/, or free-floating organisms of the sea. These

minute organisms seem like connecting-links between the two kingdoms.

They were claimed by both botanists and zoölogists until the use of

the microscope made close observation of minute structure possible.

Among the small animalcules of the phylum /Protozoa/ are some which

are familiar to all by name, such as the /Infusoria/, which are

most interesting creatures to examine in a drop of water under

the microscope. A more tangible example of the /Protozoa/ are the

/Foraminifera/. /Foraminifera/, like diatoms, have a shell-like

covering, and these shells, among the most plentiful of which are

those of the genus /Globigerina/, fall, as do those of diatoms, in

immense numbers to the bottom of the ocean, and form respectively

what are known as /Globigerina/ and diatomaceous ooze. In course of

time the sedimentary strata become fossilized; thus, the stone of

which the city of Paris is built consists of fossilized [pg022]

foraminifers, and the pyramids of Egypt are built of nummulites,

another genus of /Foraminifera/. It is estimated that an ounce of

this deposit contains four millions of these protozoans, so it is

impossible to conceive the numbers of once living animals represented

in the tombs of the Pharaohs. Telegraph-cables raised from the depth

of two miles bring the message to naturalists that the bottom of the

ocean at that depth is composed of little else than the calcareous

shells of /Foraminifera/.

Many of the lower animals resemble plants in form. Hydroids and

polyzoans are often gathered and preserved as seaweeds. Corals,

sea-anemones, and holothurians are curiously like plants. For a time

the confusion about the division of animals and plants was partly

owing to this resemblance of forms, and the theory of the animal

nature of corals was for a long time considered to be refuted by

the testimony of a naturalist who declared that he had seen them

in bloom. Later this class of animals was believed to occupy an

intermediate sphere and partake of the characteristics of both

kingdoms. The name zoöphyte, meaning "animal-plant" or "mingled

life," was adopted because of these resemblances and was formerly

applied to these forms only. To-day it has a broader application.

There is still a neutral class, called /Protista/, comprising

organisms which have not yet been classified as plants or animals.

[pg023]

V

DISTRIBUTION OF ANIMAL LIFE IN THE SEA

All living things which inhabit the sea have their appointed

boundaries, and the localization of marine life is as distinct as

is that of terrestrial life. Each kind of beach has forms of life

peculiar to itself. Those animals which inhabit rocky shores or stony

beaches or sand or mud may be looked for anywhere under similar

physical surroundings. They are, however, modified by climatic

conditions, and in wide ranges differ in genera and species. The

rocky coast of Maine has a class of sea-urchins and starfishes

which are different from those which live on the rocky shores of

the northern Pacific coast, yet they are all easily recognized as

belonging to the same family, and a description of typical forms is a

sufficient guide to the recognition of their relationships.

A bathymetrical division defines the classes of animals according

to the depth of water in which they live. Those which live near the

shore are /littoral/ species, those of the broad sea are /pelagic/,

while those living at great depths are /abyssal/.

Their modes of life are distinguished by other terms. Those which

float at or near the surface and are carried about by the currents,

like the jellyfishes and the minute organisms mentioned elsewhere,

are /plankton/. Strong swimming animals which move about at will are

/nekton/. Those which are fixed, like oysters, sponges, etc., and

those which crawl on the bottom, like crabs, echinoderms, etc., are

/benthos/.

Again, geographical divisions are named, in recognition of climatic

influences. The /boreal/ fauna and flora on the Atlantic [pg024]

coast extend from Cape Cod northward; the /American/, from Cape Cod

to Cape Hatteras; the /West Indian/, from Cape Hatteras southward. On

the Pacific coast the divisions, without definite names, are from the

Isthmus to Acapulco, Acapulco to the Gulf of California, Cape Lucas

to the Strait of Fuca. These divisions merge at indefinite lines,

but the above limits are generally accepted as the points of broad

division.

The shore or littoral fauna is especially abundant and comprises

more species that are curious in form and beautiful in color than

the others. The invertebrates of the deep sea are mostly transparent

and of a blue or violet tint, while the fishes are gray or bluish

above and white beneath, which renders them inconspicuous to their

enemies. [pg025]

VI

SOME BOTANICAL FACTS ABOUT ALGÆ

The vegetable world is separated into two great divisions:

/thallophytes/, or plants having no distinction of leaf or stem,

and /cormophytes/, or plants which have leaves and stems. All

thallophytes that live in the water and are nourished wholly by water

are called /algæ/.

A second great division of plants is into /cryptogams/, or those that

have no flowers, and /phanerogams/, or those that have flowers, by

means of which seeds are produced and successive generations of plant

life continued.

/Thallophytes/ and /cryptogams/ comprise the lowest and simplest

vegetable organisms. Algæ belong to both these divisions; to the

first because they have neither stems nor leaves, and to the second

because they have no flowers.

The lowest forms of algæ are microscopic in size, each individual

being a single cell; but in the ascending scale they attain curious

and beautiful shapes, some growing to a gigantic size and in forms

that resemble shrubs and trees. The green surface commonly seen on

the shady side of trees, on stone steps, and in other damp places is

one of the species of algæ which consist of a single cell. This plant

or cell divides, and the separate divisions divide and subdivide

again and again, and in time the aggregate number is great enough to

spread over a comparatively large surface, and thus become visible

to the naked eye. This plant, the /Pleurococcus vulgaris/, is a

fresh-water alga. The /Protococcus nivalis/, or red snow, described

on page 33, is a closely allied species. The green and blue-green

scums and slimes on [pg026] brackish ditches and on the stones and

woodwork of wharves are also species of the lowest orders of algæ

and increase by cell-division. Many of them are in colonies incased

in gelatinous matter. These, together with plants of a little higher

order, though still of low organization, the /Confervaceæ/, form a

large part of the green vegetation between tide-marks.

The vegetative body of a thallophyte is a /thallus/, and corresponds

to stem and leaf. It is also called a /frond/. What corresponds to

the root of flowering plants is in algæ a disk or conical expansion

of the base of the plant. It is simply a holdfast by which the frond

attaches itself to any submerged material. The algæ which grow on

sandy shores and on corals have holdfasts which branch like fibrous

roots and penetrate porous substances in all directions; but this

is only for greater stability, and is an adaptation to the habitat.

Holdfasts do nothing for algæ other than the name implies, whereas

real roots absorb the nourishment upon which plants live. Algæ are

nourished by the substances held in solution by the water which

surrounds them.

Algæ are the lowest and simplest in organization of all plants,

because they are composed of but one class of cells, such as in

flowering plants are called the /parenchyma/, or soft cells, these

being the ones which compose the pulp of the leaf. In the lowest

orders of algæ single cells constitute individual plants, as in

/Pleurococcus/; but in the higher forms, such as /Sargassum/, they

arrange themselves in such a variety of combinations as to resemble

plants which have leaf and stem. The botanical distinction is that in

leaf and stem there would exist the woody and the vascular cells as

well as the parenchyma cells.

Beginning with plants composed of a single cell, the next development

is into filamentous plants, which are single thread-like rows of

cells, as in /Cladophora/. In /Ulva/ is seen the earliest type of an

expanded leaf. The cells are here arranged in a horizontal surface of

plate-like or ribbon-like shape.

In /Ulva/ there is a double layer of cells. The layers separate in

/Enteromorpha/, giving a hollow or tubular form. In /Monostroma/ a

double layer is opened or torn apart, giving a frond with a single

layer of cells. [pg027]

The stem-like forms of certain algæ are composed of cylindrical

cells which combine or grow in a longitudinal direction chiefly.

Sometimes the cells are arranged evenly, in which case the stem

seems articulated, as in some species of /Ceramium/. Again, they are

irregularly placed, so that the stem appears solid.

The highest types of algæ in the differentiation of parts, or

vegetative forms, are to be found in the /Fucaceæ/, of the brown

seaweeds; the highest in the reproductive development, in the red

class.

Reproduction by cell-division, in which the organism itself breaks up

into two or more individuals, is called /vegetative reproduction/.

Higher forms reproduce by spores, or germ-cells, which give rise to

new individuals on germination.

The substance of an alga is more or less firm, according as the

vegetable mucus or gelatinous matter it contains has more or

less consistency; it is /membranaceous/ when the gelatine is

scant and glossy, /gelatinous/ when it is abundant and fluid, and

/cartilaginous/ when it is hard.

Some algæ are annuals; a few are perennials, and cast off and renew

their laminæ every season. Many plants present quite a different

appearance at different seasons of the year, and so are often

difficult to identify. Those which form spores throw off these

isolated cells, which sink or are washed to positions where they

germinate and begin their cycle of life. Many of the spores begin

their growth at once, without regard to season, so the species is

ever present. [pg028]

VII

NAMING OF PLANTS

The real or technical names of plants, which at first appear long and

unpronounceable, are in reality simple when the system of naming is

understood. Every plant has a /generic/ and a /specific/ name. The

generic name is analogous to the surname of a person, such as /Smith/

or /Jones/. The specific name is analogous to the Christian name of

a person, such as /John/ or /James/. The specific name never stands

alone, and would have as little designating character as John ---- or

James ----.

This is called the /binomial/ (two-name) /nomenclature/. It was

introduced by Linnæus, and greatly simplified the system of naming.

The rule in scientific nomenclature is that all names must be Latin

or Latinized. This gives a universal language by which scientists of

all countries understand one another.

The names of classes (the highest groups) and subclasses are

adjectives or adjective nouns, expressing the most prominent

characteristic of the class or subclass. Thus the four subclasses of

the class /Algæ/ are:

/Cyanophyceæ/ (subclass of blue-green algæ).

/Chlorophyceæ/ (subclass of grass-green algæ).

/Phæophyceæ/ (subclass of dusky-brown or olive-green algæ).

/Rhodophyceæ/ or /Florideæ/ (subclass of red algæ).

Orders are, with few exceptions, the names of genera with the

termination /-aceæ/, as:

/Ulvaceæ/, from the genus /Ulva/.

/Ectocarpaceæ/, from the genus /Ectocarpus/.

/Gigartinaceæ/, from the genus /Gigartina/. [pg029]

Suborders, or groups between orders and genera, terminate in /-eæ/.

Names of genera are nouns or words taken as nouns. They are derived

from any source,--from prominent or peculiar characteristics, from

localities, or from names of botanists,--or they may be wholly

arbitrary. Personal generic names are divested of titles and take

a final /a/, or, in many cases, for euphony, /ia/. Thus, /Ulva/ is

the Latin for "sedge"; /Ectocarpus/ is from two Greek words meaning

"fruit outside"; /Corallina/ means "coral-like"; /Grinnellia/ is

named for Mr. Henry Grinnell.

The specific names are commonly adjectives, but sometimes they are

nouns, and occasionally are the names of the botanists who first

described the plants, in which case the name terminates in /-i/ or

/-ii/. The specific name always follows the generic name, thus:

/Ectocarpus Hooperi/, a species of /Ectocarpus/, first described by

Mr. Hooper.

/Grinnellia Americana/, a species, peculiar to America, of a genus

named for Mr. Grinnell.

/Griffithsia corallina/, a species resembling coral, and belonging to

a genus named for Mrs. Griffiths.

With regard to the four subclasses mentioned above, it should be said

that algæ are strictly classified in accordance with their methods

of reproduction; but since allied species have, with few exceptions,

the same color, the classification by colors is generally adopted as

convenient and sufficiently precise.

Familiar, or, in technical language, "vulgar," names are very

generally given to land plants, and especially to flowers; but

seaweeds are less in sight than flowers are, and so, save in a

few instances, have not been named except by the man of science.

To remember the scientific names will not be found difficult, for

without effort or special pains to acquire the new vocabulary, the

names, like those of new personal friends, will insensibly become

fixed in the memory.

In the body of this work each of the groups (class, subclass, order,

etc.), in the classification of both animals and plants, is indicated

by a special kind of type. [pg030]

VIII

DISTRIBUTION OF ALGÆ

The eastern coast of North America has been divided into four

sections, which correspond to the distribution of the algæ which are

characteristic of each section. The boundary-lines are not precise,

since some species of each section extend beyond the defined limits;

but arctic forms are not generally found south of Cape Cod, nor

can tropical varieties be expected north of Cape Hatteras. On the

intervening coast, however, there are some species common to both

sections. The divisions are: (1) Greenland to Cape Cod; (2) Cape Cod

to Cape Hatteras; (3) Cape Hatteras to Cape Florida; (4) the Florida

Keys and the shores of the Gulf of Mexico.

On the Pacific coast such distinct lines of demarcation do not exist,

there being no such natural barriers as are formed on the eastern

coast, first by Cape Cod, and, second, by the stretch of sand-beach

which extends from New York to Charleston, and which divides sharply

the climatic varieties.

The whole shore is again divided laterally into three distinct belts,

called the /littoral/, the /laminarian/, and the /coralline/ zones.

The first or littoral zone covers the space between tide-marks.

Vegetable life in this zone is subjected first to exposure to the

sun and air, and even to desiccation, and then to entire submergence

at constantly recurring periods. The rockweeds (/Fucus/), which

are so plentiful in this zone, are very gelatinous, nature having

apparently provided the gelatine to protect the cells of the plant

from the effects of the alternating extreme conditions. /Fucus/ and

/Enteromorpha/ predominate in this zone. [pg031]

The laminarian zone extends from low-water mark to the depth of

fifteen fathoms. The /Laminariaceæ/ and the beautiful red algæ

(/Florideæ/) grow here.

The third or coralline zone extends to the depth of about fifty

fathoms. The algæ of this zone, the nullipores, are incrusted with

a deposit of lime which gives them the appearance of corals; and,

singularly enough, the corals, which are animal forms, simulate plant

life.

Again, algæ have special habits and demand certain climates and

seasons for their growth. Algologists register the place where a

specimen is found, and in this way localities have been pretty well

determined. However, great exactness has not been reached, and the

collector is ever watchful to find an alga in some undiscovered home

within the given range. Although algæ grow from extreme high-water

mark to the depth of fifty fathoms, almost every variety may be

found on the beach, those growing in deep water being frequently

torn off and washed ashore by the waves. The heaps of sea-wrack

will often reward one who examines them carefully for deep-water

species. Seaweeds are most abundant on rocky shores, particularly

where there are stratified rocks with crevices, which afford shelter

from the waves. Rock pools often contain beautiful varieties of the

more delicate species. Red algæ will sometimes be found on the shady

side of these pools. Sand-beaches are unfavorable to the growth of

seaweeds, but fronds which have been carried long distances by the

currents will frequently be found on such shores. [pg032]

IX

SOME PECULIAR AND INTERESTING VARIETIES OF ALGÆ

The species of seaweeds that are known and classified are said to

number several thousands. These plants, which have neither vessels

for the conduction of fluids, nor fibers, consisting simply of

the first vegetable element, the cell, have, notwithstanding this

limitation, assumed a great variety of forms. In size they vary

from one one-thousandth of an inch in diameter, the smallest green

plants known, to those which exceed in length the height of the

tallest trees and form dense submarine forests, which in places make

comparatively deep water impassable for boats. In texture they vary

from a jelly- to a paper- and a leather-like consistency. In color

they have all the shades of green, brown, and red.

DIATOMS AND OTHER MINUTE ALGÆ

Among the smallest algæ are diatoms. They are microscopic in size,

but exist everywhere in both salt and fresh water, and are infinite

in variety as well as in numbers. They have a silicious, shell-like

covering, which divides and subdivides in their reproductive growth,

forming varied shapes which are exceedingly beautiful and interesting

to examine under the microscope. In vast numbers they float on the

surface of the sea, and, together with other minute free-floating

organisms, form the basis of food-supply for fishes. Their

indestructible shells fall to the bottom of the sea, forming large

deposits, which in time become fossilized. The city of Richmond,

Virginia, is built upon [pg033] a fossiliferous bed of diatoms,

which measures twenty to eighty feet in depth and several miles in

length.

Associated with diatoms, in fresh water, are desmids, which are green

in color and resemble the diatoms except in having a cartilaginous

instead of a silicious covering. Another minute organism, /Pyrocystis

noctiluca/, is luminous and is said to produce the beautiful

phosphorescent effects seen in tropical seas. /Trichodesmium/ is a

little alga which periodically occurs in great numbers, giving the

water a red appearance, as in the Red Sea, which is said to derive

its name from this circumstance.

RED SNOW

In the high latitudes of the arctic regions, also on snowy mountains

at altitudes where all vegetable life is supposed to be extinguished,

there sometimes appears a redness on the surface of the snow, which

in some cases extends for many miles. At a certain place in Greenland

the color was so vivid that an arctic voyager named the locality the

Crimson Bluffs.

The strangeness and almost sudden appearance of this color in the

snow have been so unaccountable to uninformed observers that it has

been ascribed by them to the falling of bloody snow and has been

regarded with superstition. The redness is caused by the growth of

one of the smallest of plants, the /Protococcus nivalis/. It is a

simple one-celled alga containing protoplasm and endochrome (red

coloring-matter). It grows by cell-division, the cell dividing into

four, eight, or sixteen parts on a quaternary scale. Each part

acquires a new covering while within the mother cell, and when it

emerges it is a complete individual and ready to repeat the process.

Only a few hours are required for its growth and development; hence

its increase is rapid, and it requires but a little time to make

itself manifest in those places where the conditions are favorable to

its existence.

THE SARGASSO SEA

When the voyager reaches a certain region of the North Atlantic,

called the Sargasso Sea, he sails into a vast undulating marine

[pg034] prairie. Farther than the eye can reach is spread a

yellowish-brown vegetation which covers the water as grass covers the

plain. Sometimes these weeds are so thick as to impede navigation,

and, seen from a little distance, seem substantial enough to walk

upon. At other times, according to seasons and conditions of storm

and wind, they are divided into strips or into island-like masses,

with spaces of clear water between. If the sailor did not know the

special conditions existing here he might suppose he had come upon

dangerous shallows; or were the waters less turbulent he might dream

that he was floating among the water-weeds of an inland lake.

This vast acreage of vegetation, as large as the continent of Europe,

lying southwest of the Azores and extending between the Canary and

the Cape Verde Islands, was first reported by Columbus, and takes its

name from the floating plant of which it is composed, the /Sargassum

bacciferum/, a species of the order /Fucaceæ/, commonly known as

gulfweed. Columbus's sailors took fright at the marvelous appearance

and wished to turn back, thinking they had reached the end of the

navigable ocean. They thought, if land were beyond, it was guarded

by shoals, and that the weeds concealed dangerous rocks. Columbus

threw out two hundred fathoms of line, but did not reach bottom,

and continued on his course for fifteen days before emerging into

clear water. From that day to this the Sargasso Sea has attracted

the attention of all navigators. It is especially interesting to

scientists. The physicist finds there the phenomenon of the ocean

currents holding in a vortex this immense mass of seaweed, the

zoölogist finds a great pasture in whose protecting shelter are

living and breeding countless numbers of marine animals, and the

botanist is puzzled because the source of this species of plant is

clouded with doubt.

[Illustration: PLATE II. Macrocystis pyrifera. Agarum Turneri.

Nereocystis Lütkeana.]

According to one theory, the plants are dislodged by the tempests

from terrestrial beds and carried by the Gulf Stream into the

huge eddy; but since there does not exist enough of the attached

plants of this species to supply the vast accumulation, another and

more generally accepted theory is that the gulfweed lives also a

pelagic life and adapts itself to the conditions of the [pg035]

floating state, thus dispensing with the disk-like root, as it

needs no holdfasts, and propagating solely by lateral and axillary

ramification.

There are said to be one hundred and fifty species of /Sargassum/,

but /S. bacciferum/ alone constitutes the beds of the Sargasso Sea.

The plant is the most highly differentiated of any seaweed, in that

it more nearly approaches the true leaf and stem, and is described

botanically as follows: Frond furnished with distinct, stalked,

nerveless leaves and simple, axillary, stalked air-vessels. The

integument is leathery, and the color brown of varying shades. The

most striking peculiarity is the abundance of globular cells. These

berry-like air-bladders give the plant buoyancy enough to support the

weight of its innumerable guests. (Plate XVI.)

THE LAMINARIACEÆ

In the laminarian zone, described above, grow the /Laminariaceæ/, an

order of brown seaweeds, some of whose genera grow to enormous size,

and in some places form dense submarine forests. Darwin speaks of the

good service rendered by these plants to vessels navigating stormy

coasts, where often they act as natural breakwaters, and again as

buoys designating dangerous rocks near the shore on which they grow.

The seaweeds belonging to this order, commonly known as oarweeds,

tangle, devil's-apron, and sea-colander, are frequently seen twelve

to twenty feet in length, and others are measured by fathoms. One

of the giant plants is /Nereocystis Lütkeana/, which occurs on

the northwest coast. It has a stalk, sometimes three hundred feet

in length, which bears on its extremity a barrel- or cask-shaped

air-vessel, six or seven feet long, from the surface of which a tuft

of fifty or more forked laminæ grows to a length of thirty or forty

feet. The stem which anchors this immense frond is so small that the

Aleutian Indians use it for fishing-lines. The sea-otter makes his

home on its huge air-vessel, and the plant is called by the Russians

the "sea-otters' cabbage."

But the longest of all known plants is the alga /Macrocystis/. Its

thin naked stem, the diameter of which seldom exceeds one quarter

[pg036] of an inch, is reported by one author to be seven hundred

feet in length, by another fifteen hundred feet. It is terminated

by a lamina fifty feet long, resembling a pinnatifid leaf, each

leaflet of which, at its point of division on the stem, expands into

an air-vessel as large as an egg. These air-vessels sustain the

immense frond which floats on the surface of the water, its leaflets

depending in a vertical position from the stem. /M. pyrifera/, the

only species, is found in the Southern oceans and on the Pacific

coast of North America.

/Lessonia/, another genus, resembles a palm-tree. It grows erect to

a great height and has a stem like the bole of a tree. It branches

in a forking manner and has depending from its branches laminæ two

or three feet long. The large stems from which the laminæ have been

torn by the storms, and which have been cast ashore on the Falkland

Islands, as described by Sir Joseph Hooker, resemble driftwood, as

they lie in piles three or four feet high and extending for many

miles.

/Agarum/ and /Thalassiophyllum/ are arctic genera, but they are found

within our limits, the former in the North Atlantic. It has a simple

but enormous leaf-like frond. The latter, which is found on the North

Pacific coast, has a compound frond. Both are characterized by their

fronds being perforated throughout with holes, giving them the name

of sea-colander. [pg037]

X

USES OF ALGÆ

Water covers two thirds of the surface of the earth, and algæ, with

a very few exceptions, constitute the whole vegetation which exists

in that enormous area. They have, therefore, an important part to

perform in the economy of nature. Algæ do not, like land plants,

derive their nourishment from the soil to which they are attached,

but from substances held in solution by water. In their growth they

effect changes in the water analogous to those effected by land

plants in the air; that is, they change so-called impurities in the

water into materials essential to animal life. The function of plants

is that of transforming or manufacturing inorganic matter, which they

assimilate, into organic matter (such as starch, albumen, sugar),

which forms their own structure and which is the food essential to

animals. In this process, plants inhale carbonic acid gas which

animals breathe out, and exhale oxygen which animals breathe in.

Plants feed on mineral substances and furnish vegetable food, thus

keeping up the balance of life.

Fresh-water algæ have a like economic value. The green surface on

stagnant pools is a vegetable growth whose function is to assimilate

the matter which makes the pool offensive. A submerged district soon

becomes covered with scum, or minute plants (/Sphæoplea annulina/),

which grow with great rapidity, using up the materials of the

decaying vegetation, and in great measure counteracting the ill

effects, in the atmosphere, of such decay. When the waters subside,

the plants shrivel up and appear like thin paper covering the ground.

This ephemeral substance soon [pg038] disappears, without giving

evidence of its nature in dust or gases, its body seeming to be a

machine which transmutes, but does not hold, the substances on which

it grows.

Algæ, as has been said above, grow in definite zones, and each

zone has also a definite animal life which finds there its food.

Darwin says: "In all parts of the world a rocky and partially

protected shore perhaps supports in a given space a greater number

of individual animals than any other station." And speaking of the

/Laminariaceæ/, he adds: "I can only compare these great aquatic

forests of the southern hemisphere with the terrestrial ones in the

intertropical regions. Yet if in any country a forest was destroyed

I do not believe nearly so many species of animals would perish as

would here from the destruction of the kelp." The same may be said of

the Sargasso Sea, where millions of living creatures make their home.

In every kind of marine fauna there are species which derive, if not

the whole, at least a part of their nourishment from the seaweeds.

The vegetation in the narrow boundary of the three zones is

palpably inadequate to supply the needs of the animal life which

exists in deeper waters. But over the broad area of the ocean

there exists a vast number of pelagic, free-floating algæ, which,

although microscopical in size, are almost infinite in numbers.

In illustration of this it has been estimated that, although they

are not especially numerous in the Sargasso Sea, yet if all the

seaweed there were gathered into one mass and the free-floating

algæ into another, the bulk of the latter would exceed that of the

former. The pelagic flora consists of /Diatomaceæ/, /Protococcaceæ/,

/Peridinieæ/, and others. Undoubtedly it is on these pastures that

fishes feed, as well as other organisms which in turn are food for

fishes.

/Fucus/ and /Laminaria/ constitute the kelp from which iodine is

obtained, and were at one time the source of the potash of commerce.

/Fucus vesiculosus/ is a constituent of a medicine used as a cure for

obesity. /Chondrus crispus/, commonly known as Irish moss, was a few

years ago generally used as an article of diet. /Porphyra vulgaris/

(laver) is used by the Chinese for soups. /Rhodymenia palmata/

(dulse) is an article of food in Ireland and Scotland. [pg039]

/Gracilaria spinosa/ is used by birds, allied to the swallows, for

making their nests--the edible nests found in large numbers on the

islands of the Indian Archipelago, especially in the caves on the

shores of Java, and gathered and sent to China, where they bring

large prices and are used in making the famous birds'-nest soup.

/Gracilaria lichenoides/, also a species of the Eastern seas, is

the source of agar-agar, a preparation used in laboratories as a

culture-medium for bacteria. Fossil diatoms are ground and used for

polishing-powders. Seaweeds are everywhere used by farmers on the

coasts as fertilizers. [pg040]

XI

COLLECTING AT BAR HARBOR

The beautiful coast of Maine is a particularly good field for

shore-collecting. The rocky coast harbors the boreal fauna and flora

which depend upon such physical conditions, and the shores at Bar

Harbor are typical of those found elsewhere in northern New England.

The rocks give shelter from the beating surf, while life has exposure

to the cold, pure waters of the arctic current. Everywhere along

the shore, rock pools are to be found. These are perhaps the most

fascinating of all spots to the collector. They are veritable gardens

of the sea, where species flourish which naturally belong to deeper

water, but which find in such pools conditions suitable to their

existence.

At Bar Harbor one well-known and frequently visited rock pool is

found in Anemone Cave. Entering a field at Schooner Head, one

turns to the right and follows the rocky shore for two or three

hundred feet. It is difficult to take this short walk without being

constantly diverted and delayed by the various attractions one meets,

such as the tide-pools, the barnacles which in places whiten the

rocks, the periwinkles, the purpura shells, and the curious algæ; but

at last one arrives at a cavern under an overhanging rock. Here is a

large tide-pool which at first sight displays only a beautiful scheme

of color. It is carpeted with a bright-pink alga, /Hildenbrandtia

rosea/, which incrusts the basin of the pool.

Interspersed with the pink are patches of a deep-red color, having

a velvety appearance, which are formed by another crustaceous alga,

/Petrocelis cruenta/. The water of the pool is of crystal [pg041]

clearness, and as one gazes into it one object after another comes

into view, until one is filled with astonishment at the number of

beautiful objects the pool contains. The little green balls, one

half of an inch to one inch in diameter, which look like small green

tomatoes scattered on the stones, are /Leathesia difformis/, an

alga which cannot be mistaken for any other. Bunches of /Corallina

officinalis/, which resembles coral, as the name indicates, are

abundant. This alga should be examined with a magnifying-glass. It is

covered with calcareous matter, and its peculiar form of growth is

beautiful and interesting.

The fronds of the laminarian /Alaria esculenta/ are tiny here,

while just outside the cave they are to be seen several feet in

length, beating against the rocks in the swash of the waves. Thorny

sea-urchins (/Strongylocentrotus drobachiensis/) make green spots

which look like tufts of moss. Yellow and green sponges in little

cones are spread over small surfaces. Starfishes and ophiurans

are plentiful. The /Purpura lapillus/ and /Littorina litorea/ and

/rudis/ (periwinkles), so plentiful on this coast, are present. The

/Mytillus/ and the /Saxicava/ and the /Acmæa testudinalis/ are also

to be found. A green crab (/Carcinus mænas/) is snugly hidden in a

dark nook on the shady side of the pool, and many small crustaceans

scuttle away from under stones as they are lifted. The collector

is always anxious for uncommon, or rather less plentiful, species,

and here are found two specimens of nudibranchs, or naked mollusks,

/Æolis/ and /Dendronotus/. The /Chiton ruber/, a jointed mollusk, was

also found here, and five species of sea-anemones were counted. As

this is a favorite hunting-ground, the anemones have not been left

to attain full growth; but there are very many small ones which at

first are not distinguishable, as they retract their tentacles at the

slightest disturbance of the water and are then quite inconspicuous.

After a little time of quiet watching they will be seen putting out

their tentacles and expanding their beautiful flower-like forms.

It is useless to try to capture them uninjured, so tightly do they

adhere to the rocks, and the difficulty of preserving them in an

expanded form is so great that amateur collectors had better leave

them undisturbed to beautify the pool. [pg042]

It was hard to resist robbing this rock pool, where the author in

half an hour counted twenty different species, and finally left,

feeling that its treasures were not half discovered; but collecting

should be done elsewhere, and this pool be guarded as a gem to be

admired and not to be despoiled.

This pool in Anemone Cave, although so very attractive, is surpassed

in beauty and interest by pools on Porcupine Island, at the base

of the cliff. This place is somewhat difficult of access, and the

timid will not undertake the descent to it; but the enthusiastic

collector, who overlooks small obstacles, will be repaid by a visit

to this spot, where all the treasures of Anemone Cave are multiplied

many times over. These pools are resplendent with large anemones,

hydroids, nudibranchs, mollusks, echinoderms, crustaceans, and

algæ. /Alaria esculenta/, several feet in length, is beaten to a

fringe against the rocks, and /Agarum Turneri/, the sea-colander, is

also found here, together with beautiful specimens of /Rhodymenia

palmata/, which is so plentiful that it reddens the rocks.

A /Metridium marginatum/, the most common sea-anemone of this coast,

was taken here which measured six inches in diameter. This creature

threw out so many of the processes used for defense that it seemed at

first as though it were covered with some seaweed; but the worm-like

movements of these threads, which measured six inches or more in

length, soon disclosed their nature.

On the more accessible shores of Porcupine Island are found the naked

mollusks (nudibranchs) /Æolis/ and /Dendronotus/. Clinging sideways

to the rocks just above high-water mark are many shells of /Littorina

rudis/. They are fastened to the rocks by a glutinous deposit along

the outer lip, and the peculiar exposure of the open end, as well

as the position above tide-mark, indicates that this animal is

undergoing transformation into a land species. /Littorina palliata/

is abundant on the rockweeds (/Fucus/); some of the specimens are

banded with yellow, and all closely simulate the seaweed on which

they cling. Beautifully banded specimens of /Littorina litorea/ are

also plentiful. Among other shells which are abundant here as well as

elsewhere on this coast are /Purpura lapillus/, /Acmæa testudinalis/,

/Buccinum undatum/, /Mya arenaria/, and /Mytillus edulis/. [pg043]

Under the rockweeds in small pools and crevices are the polyzoans

/Bugula turrita/ and /Membranipora pilosa/, and the hydroids

/Sertularia pumila/ and /S. argentea/.

The seaweeds /Rhodymenia palmata/ (dulse) and /Desmarestia/ are

plentiful; also beautiful worms, crustaceans, and starfishes.

A very interesting beach is found a few hundred feet south of Otter

Cliffs, to which an easy descent is made if one follows a pathway

leading to it through a grove adjacent to the drive. Here one will be

interested in the study of numerous and beautiful rock pools.

Sea-urchins (/Strongylocentrotus drobachiensis/) seem to carpet some

of them, having the appearance of mossy tufts. Beautiful pink and

purple starfishes (/Asterias vulgaris/), brittle-stars (/Ophiopholis

aculeata/), sea-cucumbers (/Pentacta frondosa/), sea-anemones, and

crabs are abundant. If one lifts a stone the little crustaceans

/Orchestia/ and /Gammarus/ will hurry away, and very likely an

interesting worm or a nudibranch will be found. It is also most

interesting to watch the barnacles, which are below the surface,

reaching out their curled, feather-like feet in regular rhythmic

grasping motions. The common mussels (/Mytillus edulis/), which in

places blacken the shore, are beautiful under examination, and the

silky network or byssus which forms the anchorage should be observed.

The rocks are hung so plentifully with /Ascophyllum nodosum/

(rockweed) that its beauty is likely to be passed over unnoticed.

On the /Ascophyllum/ is growing in tufts /Polysiphonia fastigiata/;

other seaweeds, /Rhodymenia palmata/, /Chordaria flagelliformis/,

/Desmarestia aculeata/, /Corallina officinalis/, and /Ceramium/, are

so abundant that one forgets to value them at the moment. Higher up

on the beach the rocks are spotted with papery sheets, which, floated

out in water, prove to be the beautiful purple /Porphyra/. A fine,

dark colored, hairy scum on the rocks is /Bangia fusco-purpurea/.

Sometimes one finds here fronds of /Laminaria/ which have been washed

ashore. Various green algæ are abundant. Even if not collecting, it

is well to carry a small tin pail to the beach and float out pieces

of the algæ in order to observe carefully, if but for a moment, the

beautiful forms they have in their natural state. Watched for a few

minutes in a pail of water animals disclose curious [pg044] and

surprising forms and habits which are difficult to watch leaning over

a pool.

Most of the various species mentioned above are common along the

whole shore, and may be looked for at almost any point where the

water is free from contamination.

At the sand-beach are found species which do not inhabit the rocky

shore, as the sand-dollar (/Echinarachnius parma/), /Polynices/

(/Lunatia/) /heros/, /Mya arenaria/, and others. After a storm

various deep-water forms are washed upon this beach. /Laminaria

digitata/, six feet long, is found here sometimes under these

circumstances. /Chordaria flagelliformis/, resembling long switches

of hair, floats from the rocks near the shore. To the left, on the

rock under the overhanging ledge, is a tide-pool which one would

hesitate to deface by touching a single specimen. So crystal-clear

is the water, so brilliant the /Hildenbrandtia/, so lovely the

/Corallina/, that all seem placed there to excite admiration.

But most of all one should obtain the permission of the owner to

visit Rodicks Weir. Here is an immense natural aquarium, full of

living wonders. On a clear day, sunlight penetrates to the bottom,

and at low tide the whole contents of the weir are clearly seen as

one floats through the inclosed water-spaces. On the bottom are

sea-urchins, many of them with sticks or stones on their backs, which

the animals have placed there in the endeavor to conceal themselves;

starfishes feeding; and great numbers of whelks (/Buccinum undatum/).

Cuttlefishes dart rapidly about, and skates, sculpins, and other

fishes display their curious forms. Very likely a giant jellyfish

(/Cyanea arctica/) is entangled in the brush, so that one can examine

at short range its wonderful and beautiful parts. Other jellyfishes

may be closely scrutinized.

The alga /Polysiphonia violacea/ floats in long feathery tufts from

the stakes.

On the eel-grass are to be found /Lacuna vincta/ and the delicate

iridescent little shells of /Margarita helicina/.

Every tide brings different species of the ocean fauna to temporary

imprisonment in this inclosure, so that it is difficult to say what

one may not chance to find in this interesting place.