PART II

CLASSIFICATION OF THE SPECIES

The following classification is based on the gradual evolution of the

fruit from a cone symmetrical in form, parenchymatous in tissue,

indehiscent and deciduous at maturity, releasing its wingless seed by

disintegration--to a cone oblique in form, very strong and durable in

tissue, persistent on the tree, intermittently dehiscent, releasing its

winged seeds partly at maturity, partly at indefinite intervals during

several years. This evolution embraces two extreme forms of fruit, one

the most primitive, the other the most elaborate, among Conifers.

Two sections of the genus, Soft and Hard Pines, are distinguished by

several correlated characters, and moreover are distinct by obvious

differences in the tissues of their cones as well as in the quality and

appearance of their wood.

With the Soft Pines the species group naturally under two subsections on

the position of the umbo, the anatomy of the wood and the armature of

the conelet. In one subsection (Cembra) are found three species, P.

cembra and its allies, with the cone-tissues so completely

parenchymatous that the cones cannot release the seeds except by

disintegration. In both subsections there is a gradual evolution from a

wingless nut to one with an effective wing, adnate in one subsection,

adnate and articulate in the other. The different stages of this

evolution are so distinct that the Soft Pines are easily separated into

definite groups.

Among the Hard Pines a few species show characters that are peculiar to

the Soft Pines. These exceptional species form a subsection

(Parapinaster) by themselves.

With the remaining species, the majority of the Pines, the distinctions

that obtain among Soft Pines have disappeared. The dorsal umbo, the

articulate seed-wing, the persistent fascicle-sheath, the dorsal and

ventral stomata of the leaf and its serrate margins, the dentate walls

of the ray-tracheids have become fixed and constant. But a new form of

seed-wing appears, with a thickened blade, assuming such proportions in

P. Sabiniana and its two allies that these three constitute a distinct

group, remarkable also for the size of its cones.

Here also appear a new form of fruit, the oblique cone, and a new method

of dissemination, the serotinous cone. Associated with the latter are

the persistent cone and the multinodal spring-shoot. These characters do

not develop in such perfect sequence and regularity that they can be

employed for grouping the species without forcing some of them into

unnatural association. The oblique cone first appears sporadically here

and there and without obvious reason. The persistent cone, the first

stage of the serotinous cone, is equally sporadic in the earlier stages

of evolution. The same may be said of the multinodal shoot.

Nevertheless these characters show an obvious progression toward a

definite goal, where they are all united in a small group of species

remarkable for the form and texture of their cones, for a peculiar

seed-release and for the vigor and rapidity of their growth. It is

possible, with the assistance of other characters, to segregate these

species in three groups in which the affinities are respected and the

general trend of their evolution is preserved.

The first group, the Lariciones, contains species with large ray-pits,

cones dehiscent at maturity, and uninodal spring-shoots. They are, with

two exceptions, P. resinosa and P. tropicalis, Old World species.

The second group, the Australes, contains species with small ray-pits,

cones dehiscent at maturity and spring-shoots gradually changing, among

the species, from a uninodal to a multinodal form. They are, without

exception, species of the New World.

The third group, the Insignes, contains the serotinous species. The

ray-pits are small and the spring-shoots are, with two exceptions,

multinodal. With two exceptions, P. halepensis and P. pinaster, they are

New World species.

These three groups, being the progressive sequence of a lineal

evolution, are not absolutely circumscribed, but are more or less

connected through a few intermediate species of each group. The

systematic position of these intermediate species is determined by their

obvious affinities. It cannot be expected that the variations, which

take an important part in the evolution of the species, progress with

equal step or in perfect correlation with each other.

As to specific determinations, a little experience in the field

discloses an amount of variation in species that does not always appear

in the descriptions of authors; and species that are under the closest

scrutiny of botanists, foresters or horticulturalists, attest by their

multiple synonymy their wide variation. The possibilities of variation

are indefinite and, with adaptable Pines, the range of variation is

somewhat proportionate to change of climate. In mountainous countries,

where there are warm sheltered valleys with rich soil below cold barren

ledges, the most variable Pines are found. The western species of North

America, for instance, are much more variable than the eastern species,

while in Mexico, a tropical country with snow-capped mountains, the

variation is greatest.

Therefore in the limitation of species undue importance should not be

given to characters responsive to environment, such as the dimensions of

leaf or cone, the number of leaves in the fascicle, etc. Moreover, there

are familiar examples (P. sylvestris, etc.) that show the possibility of

wide differences in the cone of the same species.

In the following classification species only are considered without

attempting to determine varietal or other subspecific forms. But

varieties are often mentioned as one of the factors illustrating the

scope of species. Synonymy serves a like purpose, but synonyms not

conveying useful information are omitted, Roezl's list of Mexican

species, for instance, and variations in the orthography of specific

names.

PINUS

1755 Pinus Duhamel, Traite des Arbres, ii. 121.

1790 Apinus Necker, Elem. Bot. iii. 269.

1852 Cembra Opiz, Seznam, 27.

1854 Strobus Opiz, Lotos, iv. 94.

1903 Caryopitys Small, Fl. Southeast. U. S. 29.

Leaves and shoots dimorphous, primary leaves on long shoots, secondary

leaves on dwarf shoots. Flowers diclinous, the pistillate taking the

place of long shoots, the staminate taking the place of dwarf shoots.

Growth of wood and fruit emanating from the nodes; buds, branchlets and

cones, therefore, in verticillate association. Leaves and staminate

flowers in internodal position, the primary leaves along the whole

length of the internode, subtending secondary leaf-fascicles on the

apical, staminate flowers on the basal part. Buds compounded of minute

buds in the axils of bud-scales, becoming the bracts of the

spring-shoot. Branchlets of one or more internodes, each internode in

three parts--a length without leaves, a length bearing leaves and a node

of buds. Cone requiring two, rarely three years to mature, displaying

its annual growths by distinct areas on each scale. Seeds wingless or

winged, edible and nutritious.

The Pines are confined to the northern hemisphere, but grow in all

climates and under all conditions of soil, temperature and humidity

where trees can grow. Some of the species are of very restricted range,

but others are adaptable and can cover wide areas. The sixty-six species

are distributed as follows--

Eastern Hemisphere, 23.

1 exclusively African (Canary Islands).

2 exclusively European.

3 about the Mediterranean Basin.

2 common to Europe and northern Asia.

14 exclusively Asiatic.

Western Hemisphere, 43.

28 in western North America, of which 12 are confined to Mexico

and Central America.

15 in eastern North America, of which 2 are exclusively West Indian.

The two sections of the genus correspond with those of Koehne (Deutsch.

Dendrol. 28 [1893]) and his two names, Haploxylon and Diploxylon, are

adopted here, together with his two subsections of Haploxylon, Cembra

and Paracembra.

Of the two subsections of Diploxylon, Pinaster has been employed by

Endlicher (Syn. Conif. 166 [1847]) and later authors for smaller or

larger groups of Hard Pines. The subsection Parapinaster is now

proposed.

The names of groups, Cembrae, Strobi, Cembroides, Gerardianae,

Balfourianae, Pineae, Lariciones and Australes, are taken from

Engelmann's Revision of the Genus Pinus (Trans. Acad. Sci. St. Louis,

iv. 175-178 [1880]). The remainder, Flexiles, Leiophyllae, Longifoliae,

Insignes and Macrocarpae, are here proposed.

In order to bring the illustrations within the limits of the page the

dimensions of cone and leaf, as shown on the plates, are a little

smaller than life. In plates X and XXV the reproductions of the cones

are reduced to 2/5 life-size.

SECTIONS, SUBSECTIONS, AND GROUPS

Bases of the fascicle-bracts non-decurrent A--HAPLOXYLON

Umbo of the cone-scale terminal a--Cembra

Seeds wingless.

Cones indehiscent I. Cembrae

Cones dehiscent II. Flexiles

Seed with an adnate wing III. Strobi

Umbo of the cone-scale dorsal b--Paracembra

Seeds wingless IV. Cembroides

Seed-wing short, ineffective V. Gerardianae

Seed-wing long, effective VI. Balfourianae

Bases of the fascicle-bracts decurrent B--DIPLOXYLON

Fascicle-sheath or seed of Haploxylon c--Parapinaster

Fascicle-sheath deciduous VII. Leiophyllae

Fascicle-sheath persistent.

Seed-wing of the Strobi VIII. Longifoliae

Seed-wing of the Gerardianae IX. Pineae

Fascicle-sheath persistent, seed-wing

articulate, effective d--Pinaster

Base of wing-blade thin or slightly

thickened.

Cones dehiscent at maturity.

Pits of ray-cells large X. Lariciones

Pits of ray-cells small XI. Australes

Cones serotinous, pits of ray-cells small XII. Insignes

Base of wing-blade very thick XIII. Macrocarpae

HAPLOXYLON

Bases of the bracts subtending leaf-fascicles not decurrent. Staminate

flowers not sufficiently developed in the bud to be apparent.

Spring-shoots uninodal. Fibro-vascular bundle of the leaf single. Cone

symmetrical, of relatively fewer larger scales, its tissues softer.

Bark-formation late, the trunks of young trees smooth. Wood soft and

with little resin, of uniform color and with relatively obscure

definition of the annual rings. Tracheids of the medullary rays with

smooth walls.

All the species of this section, except P. Nelsonii, have deciduous

fascicle-sheaths. There are but two species of Diploxylon with

deciduous sheaths, P. leiophylla and P. Lumholtzii, both of them

easily recognized. The deciduous sheath, therefore, is an obvious and

useful means for recognizing the Soft Pines. On the characters of the

fruit and the wood Haploxylon can be divided into two subsections.

a. Cembra Umbo of the cone-scale terminal.

b. Paracembra Umbo of the cone-scale dorsal.

=Cembra=

Umbo of the cone-scale terminal. Scales of the conelet unarmed. Leaves

in fascicles of 5, the sheath deciduous, the two dermal tissues

distinct, the hypoderm-cells uniform. Pits of the cells of the wood-rays

large.

Seeds wingless.

Cones indehiscent I. Cembrae.

Cones dehiscent II. Flexiles.

Seeds with an adnate wing III. Strobi.

=I. CEMBRAE=

Seeds wingless. Cones indehiscent, deciduous at maturity.

In this group of species there is no segregation of sclerenchyma into

an effective tissue. The cones are inert under hygrometric changes and

may always be recognized in herbaria by their persistent occlusion and

soft tissues. The seeds are released only by the disintegration of the

fallen cone. There is, however, a vicarious dissemination by predatory

crows (genus Nucifraga) and rodents.

Leaves serrulate, their stomata ventral only.

Cones relatively larger, the apophyses protuberant 1. koraiensis.

Cones relatively smaller, the apophyses appressed 2. cembra.

Leaves entire, their stomata ventral and dorsal 3. albicaulis.

1. PINUS KORAIENSIS

1784 P. strobus Thunberg, Fl. Jap. 275 (not Linnaeus).

1842 P. koraiensis Siebold & Zuccarini, Fl. Jap. ii. 38.

1857 P. mandschurica Ruprecht in Bull. Acad. Sci. St. Petersb. xv. 382.

Spring-shoots more or less densely tomentose. Leaves from 8 to 12 cm.

long, serrulate, stomata ventral only, resin-ducts medial and confined

to the angles. Conelets large, subterminal, or on young trees often

pseudolateral. Cones indehiscent, from 9 to 14 cm. long,

short-pedunculate, ovoid-conical or subcylindrical; apophyses dull pale

nut-brown, rugose, shrinking much in drying and exposing the seeds,

prolonged and tapering to a more or less reflexed tip, the umbo

inconspicuous; seeds large, wingless, the spermoderm entire.

A species of the mountains of northeastern Asia with valuable wood and

large edible nuts; hardy and often cultivated in cool-temperate

climates.

The P. koraiensis of Beissner (in Nuov. Giorn. Bot. Ital. n. ser. iv.

184) and of Masters (in Gard. Chron. ser. 3, xxxiii. 34, ff.) are P.

Armandi and have led to an erroneous extension of the range of this

species into Shensi and Hupeh. In the original description of the

species the authors call attention to an error in the plate, where a

cone of another species has been substituted.

P. koraiensis resembles P. cembra in leaf and branchlet but not in the

cone. It is often confused with P. Armandi, but can easily be

distinguished by its tomentose branchlets, indehiscent cone and

peculiar seed. The two species, moreover, do not always agree in the

position of the foliar resin-ducts.

Plate VIII.

Fig. 85, Cone and seed. Fig. 86, Leaf-fascicle and magnified

leaf-section.

2. PINUS CEMBRA

1753 P. cembra Linnaeus, Sp. Pl. 1000.

1778 P. montana Lamarck, Fl. Franc. iii. 651 (not Miller).

1858 P. pumila Regel in Index Sem. Hort. Petrop. 23.

1884 P. mandschurica Lawson, Pinet. Brit. i. 61, ff. (not Ruprecht).

1906 P. sibirica Mayr, Fremdl. Wald- & Parkb. 388.

1913 P. coronans Litvinof in Trav. Mus. Bot. Acad. St. Petersb.

xi. 23, f.

Spring-shoots densely tomentose. Leaves from 5 to 12 cm. long,

serrulate; stomata ventral only; resin-ducts medial or, in the dwarf

form, often external. Conelets short-pedunculate, purple during their

second season. Cone from 5 to 8 cm. long, ovate or subglobose,

subsessile; apophyses dull nut-brown, thick, slightly convex, the margin

often a little reflexed, the umbo inconspicuous; seeds wingless, large,

the dorsal spermoderm adnate partly to the nut, partly to the

cone-scale, the ventral spermoderm wanting.

The Swiss Stone Pine attains a height of 15 or 25 metres and occupies

two distinct areas, the Alps, from Savoy to the Carpathians at high

altitudes, and the plains and mountain-slopes throughout the vast area

from northeastern Russia through Siberia. Beyond the Lena and Lake

Baikal it becomes a dwarf (var. pumila) with its eastern limit in

northern Nippon and in Kamchatka. It is successfully cultivated in the

cool-temperate climates of Europe and America. The wood is of even,

close grain, peculiarly adapted to carving. The nuts are gathered for

food and confections, but are destroyed in great numbers by squirrels,

mice and a jay-like crow, the European Nutcracker. It is generally

conceded, however, that these enemies assist in dissemination.

Plate VIII.

Fig. 87, Cone, seed and magnified leaf-section. Fig. 88, Tree at

Arolla, Switzerland. Fig. 89, Cone, leaf-fascicle and magnified

leaf-section of var. pumila.

3. PINUS ALBICAULIS

1853 P. flexilis Balfour in Bot. Exped. Oregon, 1, f. (not James).

1857 P. cembroides Newberry in Pacif. R. R. Rep. vi-3, 44, f.

(not Zuccarini).

1863 P. albicaulis Engelmann in Trans. Acad. Sci. St. Louis, ii. 209.

1867 P. shasta Carriere, Trait. Conif. ed. 2, 390.

Spring-shoots glabrous or pubescent. Branchlets pliant and tough. Leaves

from 4 to 7 cm. long, entire, stout, persistent for several years;

stomata dorsal and ventral; resin-ducts external. Conelets

short-pedunculate, dark purple during the second season, their scales

often tapering to an acute apex. Cones from 5 to 7 cm. long, subsessile,

oval or subglobose; apophyses nut-brown or fulvous brown, dull or

slightly lustrous, very thick, the under surface conspicuous, meeting

the upper surface in an acute margin, and terminated by a salient,

often acute umbo; seed wingless, the testa bare of spermoderm.

This species ranges from British Columbia through Washington and

Oregon, over the mountains of northern California and the Sierras as

far south as Mt. Whitney, and, on the Rocky Mountains, through Idaho

and Montana to northern Wyoming. It is found at the timber-line of

many stations and forms, in exposed situations, flat table-like masses

close to the ground. It is a species of no economical importance and

is too inaccessible for the profitable gathering of its large nuts,

which are devoured in quantity by squirrels and by Clark's crow, a

bird of the same genus with the pinivorous Nutcracker of Europe.

P. albicaulis is distinguished from its allies by its entire leaves

with both dorsal and ventral stomata, from P. flexilis by its

indehiscent cone, and from all of these species by its seed without

membranous cover or rudimentary wing. It was united with P. flexilis

by Parlatore and Gordon, and, later, was referred to that species as a

varietal form by Engelmann (in Brewer & Watson, Bot. Calif. ii. 124).

Parrish's P. albicaulis (in Zoe, iv. 350), extending its range to the

mountains of southern California, proves to be P. flexilis (Jepson,

Silva Calif. 74).

Plate VIII.

Fig. 90, Two cones and seed. Fig. 91, Leaf-fascicle. Fig. 92,

Magnified leaf-section.

[Illustration: PLATE VIII. P. KORAIENSIS (85, 86), CEMBRA (87-89),

ALBICAULIS (90-92)]

=II. FLEXILES=

Seeds wingless, the spermoderm forming a narrow border with a

rudimentary prolongation. Cones dehiscent at maturity.

The dehiscent cone distinguishes this group from the Cembrae.

Therefore confusion of P. koraiensis with P. Armandi, or P. albicaulis

with P. flexilis should be impossible. The peculiar seed is found

again only in the northern variety of P. ayacahuite.

Leaves usually entire, the stomata dorsal and ventral 4. flexilis.

Leaves serrulate, the stomata ventral only 5. Armandi.

4. PINUS FLEXILIS

1823 P. flexilis James in Long's Exped. ii. 34.

1882 P. reflexa Engelmann in Bot. Gaz. vii. 4.

1897 P. strobiformis Sargent, Silva N. Am. xi. 33, tt. 544, 545

(not Engelmann).

Spring-shoots pubescent; branchlets very tough and pliant. Leaves from 3

to 9 cm. long, entire, or serrulate in the southern variety, persistent

for five or six years; stomata dorsal and ventral or, in the south,

sometimes ventral only; resin-ducts external. Cones from 6 to 25 cm.

long, ovate or subcylindrical, short-pedunculate; apophyses pale tawny

yellow, or yellow ochre, lustrous, often prolonged and more or less

reflexed, thick, the margin together with the umbo raised above the

surface of the cone.

This species grows on the Rocky Mountains from Alberta in the Dominion

of Canada to Chihuahua in northern Mexico and ranges westward to the

eastern slope of the Sierras and to the southern mountains of

California. The wood, where accessible, is manufactured into lumber.

It may be seen in the Arnold Arboretum and in the Royal Gardens at

Kew.

P. flexilis is recognized by its lustrous yellow cones. This and the

constantly external ducts of its usually entire leaves distinguish it

from P. Armandi. From P. albicaulis, with similar leaves, it differs

by its dehiscent cone. At one extreme the cone of P. flexilis is not

unlike that of P. albicaulis, at the other extreme it approaches the

characteristic cone of P. ayacahuite, with prolonged reflexed scales.

Hence the confusion of P. albicaulis with P. flexilis (Murray,

Parlatore and others) and of P. flexilis with Engelmann's P.

strobiformis. Sargent's P. strobiformis, illustrated in the Silva of

North America, is the form of this species known as var. reflexa of

Engelmann.

Plate IX.

Fig. 93, Two cones and seed. Fig. 94, Leaf-fascicle. Fig. 95,

Magnified leaf-section.

5. PINUS ARMANDI

1884 P. Armandi Franchet in Nouv. Arch. Mus. Paris, ser. 2,

vii. 95, 96, t. 12.

1898 P. scipioniformis Masters in Bull. Herb. Boiss. vi. 270.

1903 P. koraiensis Masters in Gard. Chron. ser. 3, xxxiii. 34,

ff. 18, 19 (not Siebold & Zuccarini).

1908 P. Mastersiana Hayata in Gard. Chron. ser. 3, xliii, 194.

Spring-shoots glabrous; branches and most of the trunk covered with a

smooth gray cortex. Leaves from 8 to 15 cm. long, serrulate; stomata

ventral only; resin-ducts external, external and medial, or medial, all

three conditions sometimes occurring in leaves of the same branchlet.

Cones from 6 to 20 cm. in length, pendent on peduncles of various

lengths, the peduncle often remaining on the tree after the fall of the

cone; apophyses fulvous brown, dull or sublustrous, the margin rounded

or tapering to an acute apex, sometimes a little prolonged and reflexed,

the umbo inconspicuous.

A tree of the mountains of central, southern and western China with an

outlying station on the Island of Formosa. Recently planted in Europe

and America, it has so far proved hardy. The nuts are gathered for

food and some use is made of the wood.

The glabrous shoots of P. Armandi distinguish it from P. flexilis and

P. koraiensis. From the latter it is also distinct in its dehiscent

cone and in its seed. The section of its leaf, with dorsal ducts often

in two positions, is peculiar to this species among Soft Pines.

Plate IX.

Fig. 96, Two cones and seed. Fig. 97, Leaf-fascicle. Figs. 98, 99,

Magnified sections of three leaves.

[Illustration: PLATE IX. P. FLEXILIS (93-95), ARMANDI (96-99)]

=III. STROBI=

Seed with a long effective wing adnate to the nut.

The base of the seed-wing corresponds to the marginal spermoderm of the

Flexiles but is prolonged into an effective adnate wing. This form of

wing appears again in the species Balfouriana and in the group

Longifoliae.

Cones very long, usually exceeding 25 cm.

Cone-scales prolonged and reflexed 6. ayacahuite.

Cone-scales appressed 7. Lambertiana.

Cones less than 25 cm. long.

Cone-scales prominently convex.

Leaves less than 7 cm. long 8. parviflora.

Leaves 9-12 cm. long 9. peuce.

Leaves 12-18 cm. long 10. excelsa.

Cone-scales thin, conforming to the surface of

the cone.

Cone relatively longer, its phyllotaxis 8/21 11. monticola.

Cone relatively shorter, its phyllotaxis 5/13 12. strobus.

6. PINUS AYACAHUITE

1838 P. ayacahuite Ehrenberg in Linnaea, xii. 492.

1848 P. strobiformis Engelmann in Wislizenus, Tour Mex. 102.

1857 P. Veitchii Roezl, Cat. Graines Conif. Mex. 32.

1858 P. Bonapartea Roezl in Gard. Chron. 358.

1858 P. Loudoniana Gordon, Pinet. 230.

Spring-shoots glabrous or pubescent. Leaves from 10 to 20 cm. long,

serrulate, their stomata ventral only, their resin-ducts external, often

numerous. Cones from 25 to 45 cm. long, pendent on long stalks,

subcylindrical or tapering, often curved; apophyses pale nut-brown, dull

or sublustrous, varying much in thickness, prolonged in various degrees,

the prolongations patulous, reflexed, recurved or revolute; seeds of

the southern typical form with a long wing, the wing diminishing and the

nut increasing in relative size northward.

The White Pine of Mexico and Guatemala grows on mountain-slopes and at

the head of ravines. It is not very hardy in cultivation except in the

milder parts of Great Britain and in northern Italy, where the forms

of central and northern Mexico have been very successful. The species

is best recognized by the prolonged apophyses of its large cone.

The variations in the size of the cone and in the prolongations of its

scales are many, but of far more significance is the remarkable

variation of the seed-wing, which is long in the southern part of the

range, short and broad in central Mexico, and rudimentary, like the

seed of P. flexilis, in the north. This makes it possible to establish

two well defined varieties--Veitchii and brachyptera. The three forms

of the species present a gradation from the long effective wing of the

Strobi to the rudimentary form of the Flexiles. Many of the seed-wings

of the var. Veitchii correspond, in their short broad form and opaque

coloring, with the characteristic wing of P. Lambertiana.

Plate X. (leaves and cones much reduced).

Fig. 103, Cone and cone-scale of var. Veitchii. Fig. 104, Cone and

seed of var. brachyptera. Fig. 105, Cone-scale of the typical form.

Figs. 106, 107, Leaf-fascicles and magnified leaf-sections.

7. PINUS LAMBERTIANA

1827 P. Lambertiana Douglas in Trans. Linn. Soc. xv. 497.

Spring-shoots pubescent. Leaves from 7 to 10 cm. long, serrulate;

stomata dorsal and ventral; resin-ducts external or with one or two

ventral medial ducts. Cones from 30 to 50 cm. long, pendent,

subcylindrical, tapering to a rounded apex; apophyses pale nut-brown,

thick, a narrow border of the under surface showing on the closed cone,

the margin rounded or tapering to a blunt slightly reflexed tip; seed

with a large nut and a broad short opaque wing.

The Sugar Pine is the tallest of the genus and attains a height of 50

or 60 metres. It grows on mountain slopes and the sides of ravines.

Its southern limit is in Lower California on the plateau of San Pedro

Martir, its northern limit is in western Oregon. The wood is valuable,

its nuts are eaten by native Indians, and the sweet exudation, which

gives the tree its popular name, is a manna-like substance of some

officinal value. P. Lambertiana is recognized by its long cone and by

the constant dorsal stomata of its leaves.

Plate X. (leaves and cone much reduced).

Fig. 100, Cone and seed. Fig. 101, Conelet. Fig. 102, Leaf-fascicle

and magnified leaf-section.

[Illustration: PLATE X. P. LAMBERTIANA (100-102), AYACAHUITE (103-107)]

8. PINUS PARVIFLORA

1784 P. cembra Thunberg, Fl. Jap. 274. (not Linnaeus).

1842 P. parviflora Siebold and Zuccarini, Fl. Jap. ii. 27, t. 115.

1890 P. pentaphylla Mayr, Mon. Abiet. Jap. 78, 94, t. 6.

1908 P. morrisonicola Hayata in Gard. Chron. ser. 3, xliii. 194.

1908 P. formosana Hayata in Jour. Linn. Soc. xxxviii. 297, t. 22.

Spring-shoots pubescent or glabrous; branches becoming studded with

prominent resin-cells of the cortex. Leaves from 3 to 8 cm. long,

slender, serrulate; stomata ventral only; resin-ducts external and

dorsal. Cones subsessile, often persistent, from 5 to 10 cm. long,

patulous or horizontal, short-ovate, or elongate and slightly conical;

apophyses nut-brown, abruptly convex near the apex, or irregularly

warped, varying much in size, the umbo confluent with the thin margin of

the scale and resting on the apophysis beneath; seeds with a large nut

and a short broad wing, often temporarily adherent to the cone-scale and

breaking apart at the fall of the nut.

A tree of the mountains of Japan and Formosa, cultivated extensively.

It is recognized by its very short quinate leaves and by its nearly

sessile cones. The frequent but not invariable retention of the

seed-wing in the cone is due to adhesion. Many seeds fall with their

wings intact, others break away from the wing which, after a while,

loosens and also falls.

Plate XI.

Figs. 114, 115, Three cones and seed. Fig. 116, Leaf-fascicle and

magnified leaf-section.

9. PINUS PEUCE

1844 P. peuce Grisebach, Spicil. Fl. Rumel. ii. 349.

1865 P. excelsa Hooker in Jour. Linn. Soc. viii. 145. (not Wallich).

Spring-shoots glabrous. Leaves from 7 to 10 cm. long, erect, serrulate;

stomata ventral only; resin-ducts external. Connective of pollen-sacs

small and narrow. Cones deciduous, from 8 to 15 cm. long,

subcylindrical, often curved, the peduncle short; apophyses tawny

yellow, prominently and abruptly convex, the umbo against the scale

beneath; seed-wing long.

A tree of the Balkan Mountains, very hardy and bearing abundant fruit

in the gardens of both hemispheres. The cone resembles that of P.

excelsa, but is prevalently much shorter and with a relatively shorter

peduncle. Its leaves are also much shorter and are always erect. A

curious difference is found in the connectives of the pollen-sacs,

small in peuce (fig. 113), large in excelsa (fig. 110). The convexity

of its apophyses distinguishes the cone from those of P. monticola and

P. strobus. Beissner followed Hooker and named this species excelsa,

var. peuce, in the first edition of his Handbuch (1891), but in the

second edition he restored the Balkan Pine to specific standing.

Plate XI.

Fig. 111, Cone and seed. Fig. 112, Leaf-fascicle and magnified

leaf-section. Fig. 113, Pollen-sacs and connective magnified.

10. PINUS EXCELSA

1824 P. excelsa Wallich ex Lambert, Gen. Pin. ii, 5, t. 3.

1845 P. nepalensis De Chambray, Arbr. Resin. 342.

1854 P. Griffithii McClelland in Griffith, Notul. Pl. Asiat. iv, 17;

Icon. Pl. Asiat. t. 365.

Spring-shoots glabrous. Leaves from 10 to 18 cm. long, drooping,

serrulate; stomata ventral only; resin-ducts external but often with a

medial ventral duct. Connective of the pollen-sacs large. Cones from 15

to 25 cm. long, narrow-cylindrical; apophyses tawny yellow or pale

fulvous brown, prominently convex, the umbo against the apophysis

beneath; seeds with a long wing.

A tree with gray-green drooping foliage, found, with some

interruptions, along the Himalayas. It furnishes resin, tar and wood

of considerable value. It is cultivated in all temperate climates and

is a familiar tree of American and European gardens. Madden states

that the foliage of P. excelsa is sometimes erect and is occasionally

bright green. Such variations are often met in other species of Pinus.

Usually the drooping gray-green foliage and the peculiar cone are

sufficient for the recognition of this species. The not infrequent

presence of a medial duct and the large connective are valuable aids

for identifying it.

Plate XI.

Fig. 108, Cone and seed. Fig. 109, Leaf-fascicle and magnified

section of two leaves. Fig. 110, Pollen-sacs and connective

magnified.

[Illustration: PLATE XI. P. EXCELSA (108-110), PEUCE (111-113),

PARVIFLORA (114-116)]

11. PINUS MONTICOLA

1837 P. monticola Douglas ex Lambert, Gen. Pin. iii. t.

1884 P. porphyrocarpa Lawson, Pinet. Brit. i, 83, ff.

Spring-shouts pubescent. Leaves from 4 to 10 cm. long, serrulate;

stomata ventral or rarely with a few dorsal stomata; resin-ducts

external. Cones from 10 to 25 cm. long, cylindrical or tapering,

sometimes curved; apophyses brown-ochre or fulvous brown, thin, smooth,

conforming to the surface of the cone, the apex sometimes slightly

prolonged and reflexed, the umbo not quite touching the surface of the

scale below.

The western White Pine grows in southern British Columbia and on

Vancouver Island, on the Rocky Mountains of Montana and Idaho, in

Washington, on the Blue Mountains, Cascades and Coast Range of Oregon,

across northern California and along the Sierras to the mountains of

southern California. Where it is abundant and accessible it furnishes

valuable timber. It is hardy in New England and in northern and

central Europe.

It differs from P. strobus in the higher phyllotaxis of its cone, an

obvious difference that may be seen by comparing cones of the two

species of the same length (figs. 117, 119), the number of scales on

the cone of P. monticola being much greater than that on the cone of

P. strobus. Nuttall (Sylva, iii, 118) followed Hooker in considering

it to be a variety of P. strobus.

Plate XII.

Fig. 117, Cone and cone-scale. Fig. 118, Leaf-fascicle and magnified

leaf-section.

12. PINUS STROBUS

1753 P. strobus Linnaeus, Sp. Pl. 1001.

1855 P. nivea Booth ex Carriere, Trait. Conif. 305.

1862 P. alba-canadensis Provancher, Fl. Canad. ii. 554.

1903 Strobus strobus Small, Fl. Southeast. U. S. 29.

Spring-shoots pubescent. Leaves from 6 to 14 cm. long, serrulate;

stomata ventral only; resin-ducts external. Cones from 8 to 24 cm. long,

narrow cylindrical, sometimes curved; apophyses fulvous brown, or rufous

brown, thin, the smooth or slightly rugose surface conforming to the

general surface of the cone; seed with a long wing.

A valuable timber-tree of singular beauty and rapid growth. The

northern limit of its range extends from Newfoundland to Manitoba; it

grows throughout the northern states from Minnesota to the Atlantic,

and, south of Pennsylvania, along the Appalachians to northern

Georgia. Its tractable and reliable wood, its adaptability to various

soils and climates, its early maturity and stately habit, recommend it

to the forester and gardener.

Mature trees of P. strobus tower above the evergreens associated with

it. It is also recognized by the color and horizontal massing of its

foliage. The cone, when closed, is very narrow; its thin flat scales

distinguish it from the cone of P. peuce, and its phyllotaxis from the

cone of P. monticola. To illustrate the possibilities of variation in

the size of Pine cones, I once collected several in Tamworth, N. H.,

on the estate of Mr. Augustus Hemenway, on the same slope and within

an area of one square kilometre. These cones varied in length from 6

to 24 cm., with all intermediate sizes. Also on each tree were cones

of various lengths, but the longest were confined to two or three

trees among the several hundred examined. Dimensions of leaves also

varied with individual trees; not infrequently the leaves of a tree

were twice the length of those of an adjacent tree. Such variations

appear in many species and in many localities.

Plate XII.

Fig. 119, Two cones. Fig. 120, Leaf-fascicle. Fig. 121, Magnified

leaf-section. Fig. 122, Conelets. Fig. 123, A cultivated tree in

Massachusetts.

[Illustration: PLATE XII. P. MONTICOLA (117, 118), STROBUS (119-123)]

=Paracembra=

Umbo of the cone-scale dorsal. Scales of the conelet mucronate or

aristate. Epiderm and hypoderm of the leaf similar, appearing as a

single tissue; resin-ducts external. Pits of the ray-cells small.

The wood of this subsection differs from that of other species, except

that of P. pinea, in the Picea-like characters of the medullary

rays--tracheids with smooth walls combined with the thick walls and

small pits of the ray-cells. On the character of the seeds the species

may be divided into three groups.

Seeds wingless IV. Cembroides.

Seeds with a short, ineffective, articulate wing V. Gerardianae.

Seeds with a long and effective wing VI. Balfourianae.

=IV. CEMBROIDES=

Seeds wingless, the nut large, wholly or partly bare of membranous

cover. Cones varying from yellow-ochre to deep red-orange in color.

These are the Nut Pines, growing on the arid slopes and table-lands

above the great plateau of northern Mexico and its extension into the

southwestern United States. There are three distinct species.

Leaves entire, the sheath deciduous.

Cones subglobose, subsessile 13. cembroides.

Cones cylindrical, pedunculate 14. Pinceana.

Leaves serrulate, the sheath persistent 15. Nelsonii.

13. PINUS CEMBROIDES

1832 P. cembroides Zuccarini in Abh. Akad. Muench. i. 392.

1838 P. Llaveana Schiede in Linnaea, xii. 488.

1845 P. monophylla Torrey in Fremont's Rep. 319, t. 4.

1847 P. Fremontiana Endlicher, Syn. Conif. 183.

1848 P. edulis Engelmann in Wislizenus, Tour. Mex. 88.

1848 P. osteosperma Engelmann in Wislizenus, Tour. Mex. 89.

1862 P. Parryana Engelmann in Am. Jour. Sci. ser. 2, xxxiv. 332

(not Gordon).

1897 P. quadrifolia Sudworth, Bull. 14, U. S. Dep. Agric. 17.

1903 Caryopitys edulus Small, Fl. Southeast. U. S. 29.

Spring-shoots pruinose. Leaves from 2 to 6 cm. long, in fascicles of 1

to 5, the sheath-scales revolute at the apex, then deciduous; stomata

ventral, or ventral and dorsal; resin-ducts external. Scales of the

conelet armed with a minute prickle. Cones from 4 to 6 cm. long,

subglobose, subsessile; apophyses lustrous ochre-yellow, crowned with a

quadrilateral umbo bearing the minute prickle of the conelet; seed

flaxen yellow when fresh, its testa bare, the spermoderm adnate to the

cone-scale.

A broad tree with a round head, similar in size and form, but not in

ramification, to the cultivated Apple-tree; growing on arid slopes and

table-lands. Its eastern limit is in southwestern Wyoming, central

Colorado, Texas, western Tamaulipas and northwestern Vera Cruz. It

ranges over Utah, Nevada, Arizona and the northern states of Mexico to

the southern Sierras of California and to the northern and southern

extremities of Lower California. It is recognized by its small cone,

which expands, when open, into an irregular flat aggregate of loosely

attached scales. The leaves are shorter than those of the other Pines

of this group.

The cone of this species always retains its peculiar character. The

variations are mainly in the number of leaves in the fascicle. On this

character this Nut Pine is divided by many authors into four

species--cembroides, with three slender leaves--edulis, with two stout

leaves--monophylla, with one leaf and--Parryana, with four stout

leaves. But there are intermediate forms that may be either cembroides

or edulis, edulis or monophylla etc., and Voss's reduction of the four

to a single species with three varieties seems to be justified (Mitt.

Deutsch. Dendrol. Ges. xvi. 95).

Plate XIII.

Fig. 130, Cone, cone-scale and seed. Fig. 131, Open cone. Fig. 132,

Branchlet with leaves and magnified leaf-section.

14. PINUS PINCEANA

1846 P. cembroides Gordon in Jour. Hort. Soc. Lond. i. 236, f.

(not Zuccarini).

1858 P. Pinceana Gordon, Pinet. 204.

1882 P. latisquama Engelmann in Gard. Chron. ser. 2, xviii. 712.

f. 125 (as to cone only).

Spring-shoots slender, pruinose. Leaves in fascicles of three, the

sheath revolute at the base, then deciduous; stomata ventral, or ventral

and dorsal; resin-ducts external. Scales of the conelet minutely

mucronate. Cones from 6 to 9 cm. long, cylindrical, pendent on long

peduncles; apophyses lustrous ochre-yellow, elevated in the centre,

the umbo usually retaining the small prickle; seed large, bearing on its

dorsal surface remnants of the spermoderm.

A small bushy tree with long slender branchlets, clear gray cortex,

persistently smooth except on the lower part of the trunk, and

glaucous-green foliage. It grows along water-courses, dry in autumn

and winter, from southern Coahuila to central Hidalgo, and is

associated with P. cembroides, from which it may be distinguished by

its longer leaves and much longer cylindrical cone.

Plate XIII.

Fig. 127, Cone, cone-scale and seed. Fig. 128, Branchlet with

leaves. Fig. 129, Magnified leaf-section.

15. PINUS NELSONII

1904 P. Nelsonii Shaw in Gard. Chron. ser. 3, xxxvi. 122, f. 49.

Spring-shoots slender, pruinose; branchlets very pliant and tough,

summer-shoots abundant. Leaves with a persistent sheath, from 6 to 9 cm.

long, united in threes along a portion of their ventral surface into

pseudomonophyllous fascicles, serrulate on the two margins of the dorsal

surface, entire on the ventral margin; stomata dorsal and with one row

along the free portion of each ventral face. Conelets usually, if not

always, pseudolateral by reason of the summer growth of the branchlets,

and attaining in their first season an unusually large size. Cones from

6 to 12 cm. long, on very long stout and curved peduncles, cylindrical,

deciduous by an articulation between the cone and its peduncle, leaving

the latter for several years on the tree; apophyses dark lustrous

orange-red, rugose, elevated along a sharp transverse keel, the umbo

obscurely defined, the mucro usually broken away; nuts large, flaxen

yellow, the spermoderm adnate to the cone-scale.

A small bushy tree with long pliant branches, clear gray cortex all

over the limbs and trunk, and sparse gray-green foliage. It grows,

together with P. cembroides, on the lower slopes of the northeastern

Sierras of Mexico, near the boundary between the states of Tamaulipas

and Nuevo Leon. It is apparently confined to a small area near the

latitude of the city of Victoria, the capital of Tamaulipas, where its

nuts are often exposed for sale.

In many characters this species is unique. It can be recognized at

once by the connate leaves that form the fascicle or by the remarkable

stout curved peduncle of its cone. Such seeds as I have seen differ

from those of P. cembroides by a reddish area at one end, but this can

be seen with fresh seeds only.

Plate XIII.

Fig. 124, Cone, cone scale and seed. Fig. 125, Branchlet with

leaves. Fig. 126, Magnified section of a leaf-fascicle.

[Illustration: PLATE XIII. P. NELSONII (124-126), PINCEANA (127-129),

CEMBROIDES (130-132)]

=V. GERARDIANAE=

Seeds with a very short ineffective articulate wing. Leaves in fascicles

of 3, serrulate, the sheath deciduous. Bark exfoliating in large scales,

leaving parti-colored areas.

These Asiatic Nut Pines are alike in leaf and cortex as well as in the

peculiar seed-wing. The last often remains in the cone after the nut

falls. The mechanical nature of this adhesion is apparent in P.

Gerardiana, where the wing adheres not to its own, but to the adjacent

scale. The two species are alike in their leaves but distinct in their

cones and seeds.

Cones smaller, the nut short-ovate 16. Bungeana.

Cones larger, the nut long-cylindrical 17. Gerardiana.

16. PINUS BUNGEANA

1847 P. Bungeana Zuccarini ex Endlicher, Syn. Conif. 166.

Spring-shoots glabrous, summer-shoots common on fruiting branches of

young trees. Leaves from 6 to 10 cm. long, serrulate; stomata dorsal and

ventral; resin-ducts external. Conelets subterminal or often

pseudolateral, their scales gradually narrowed into a spine. Cones from

5 to 7 cm. long, short-pedunculate, short-ovate; apophyses dull pale

nut-brown, elevated along a transverse keel, the dark brown umbo forming

a spine with a broad base; seeds with a short loosely attached wing,

sometimes remaining in the cone when the short-ovate nut falls.

A tree cultivated about the temples of China and recently found by

Wilson growing on the mountains of Hupeh. The earlier parti-colored

bark changes to chalky white on old trunks, by which the tree is

recognized from a great distance. The stem of the tree is often

multiple by the vertical growth of some of the lower branches. It is

very hardy and is cultivated in Europe and America, although these

cultivated trees are not yet of sufficient age to show the remarkable

white trunk.

Plate XIV.

Fig. 138, Cone and cone-scale with adhering wing. Fig. 139, Seed and

wing. Fig. 140, Leaf-fascicle and magnified leaf-section. Fig. 141,

Parti-colored bark. Fig. 142, Tree with white trunk.

17. PINUS GERARDIANA

1832 P. Gerardiana Wallich ex Lambert, Gen. Pin. ed. 8vo, ii. t. 79.

Spring-shoots glabrous. Leaves from 6 to 10 cm. long, serrulate; stomata

dorsal and ventral; resin-ducts external. Scales of the conelet armed

with a short spine. Cones from 9 to 15 cm. long, short-pedunculate,

ovoid or oblong; apophyses fulvous brown, very thick, with a prominent

reflexed or erect protuberance culminating in an umbo on which the spine

is more or less persistent; nuts remarkably long, narrow, terete, the

shell fragile, the short wing falling with the nut or adhering to the

adjacent scale.

A tree of the northwestern Himalayas found on the borders of Cashmere

and Thibet and in Kafiristan and north Afghanistan, and so highly

prized for its nuts that it is rarely felled for its wood. It grows in

dry regions and rarely attains a height of 20 metres. Attempts to

cultivate this species, even in the milder parts of Great Britain,

have generally failed.

The apophysis of the cone varies much in prominence (figs. 134, 135),

but the peculiar seed is invariable and quite unlike that of any other

Pine. The general color of the trunk at a distance is silver-gray.

Plate XIV.

Fig. 133, Cone. Fig. 134, Cone-scale with adhering seed-wing. Fig.

135, Cone-scale of flatter form. Fig. 136, Seed and wing. Fig. 137,

Leaf-fascicle and magnified leaf-section.

[Illustration: PLATE XIV. P. GERARDIANA (133-137), BUNGEANA (138-142)]

=VI. BALFOURIANAE=

Seeds with long effective wings. Leaves entire, in fascicles of 5, the

sheath deciduous.

The two species known as Foxtail Pines are alike in their short entire

falcate leaves, persisting for many years and forming long dense

foliage-masses. They differ in the armature of their cones and in

their seed-wings. The presence of both adnate and articulate wings in

these closely related species suggests that these two forms of wing

are not fundamentally distinct.

Cone-scales short-mucronate, the seed-wing adnate 18. Balfouriana.

Cone-scales long-aristate, the seed-wing articulate 19. aristata.

18. PINUS BALFOURIANA

1853 P. Balfouriana Balfour in Bot. Exp. Oregon, 1, f.

Spring-shoots somewhat puberulent. Leaves from 2 to 4 cm. long,

persistent for many years; stomata ventral only; resin-ducts external.

Scales of the conelet short-mucronate. Cones from 7 to 12 cm. long,

tapering to a rounded apex, short-pedunculate; apophyses dark

terracotta-brown, tumid, the umbo bearing a short recumbent prickle;

seed with a long adnate wing.

An alpine species growing often at the timber-limit. It is found in

two distinct stations in California, on the northern Coast Range and

on the southern Sierras. It is not often cultivated, but young plants

may be seen in the Arnold Arboretum and in the Royal Gardens at Kew.

Plate XV.

Fig. 147, Cone, seed and enlarged cone-scale. Fig. 148,

Leaf-fascicle. Fig. 149, Magnified leaf-section. Fig. 150, A branch

with persistent leaves.

19. PINUS ARISTATA

1862 P. aristata Engelmann in Am. Jour. Sci. ser. 2, xxxiv. 331.

1871 P. Balfouriana Watson in King's Rep. v. 331 (not Balfour).

Spring-shoots glabrous or temporarily pubescent. Leaves from 2 to 4 cm.

long, persistent for many years; stomata ventral only; resin-ducts

external. Scales of the conelet prolonged into long slender bristles.

Cones from 4 to 9 cm. long, subcylindrical or tapering to a rounded

apex, short-pedunculate; apophyses terracotta or purple-brown, tumid,

the long bristles of the umbo often partly or wholly broken away; seeds

with a long articulate wing.

A bushy tree, similar in foliage to the preceding species, growing at

the timber-limit from Colorado through Utah, central and southern

Nevada and northern Arizona into southeastern California, but

separated from the nearest station of P. Balfouriana by an arid

treeless desert. Engelmann (in Brewer and Watson, Bot. Calif. ii. 125)

considered it to be a variety of P. Balfouriana.

Plate XV.

Fig. 143, Cone. Fig. 144, Seed and enlarged cone-scale. Fig. 145,

Leaf-fascicle and magnified leaf-section. Fig. 146, Conelet.

[Illustration: PLATE XV. P. ARISTATA (143-146), BALFOURIANA (147-150)]

DIPLOXYLON

Bases of the bracts subtending leaf-fascicles decurrent. Leaves

serrulate; fibro-vascular bundle double; stomata dorsal and ventral.

Cones with a dorsal umbo, the phyllotaxis complex. Wood hard, with dark

resinous bands, the annual rings clearly defined.

In this section there are a few species combining the essential

characters of Diploxylon with important characters of Haploxylon. A

subsection, Parapinaster, is established for these exceptional

species.

c. Parapinaster Species with the fascicle-sheath or seed-wing of

Haploxylon.

d. Pinaster Sheath persistent, seed-wing articulate, effective.

=Parapinaster=

Sheath of the leaf-fascicle deciduous VII. Leiophyllae.

Sheath of the leaf-fascicle persistent.

Seed-wing of the Strobi VIII. Longifoliae.

Seed-wing of the Gerardianae IX. Pineae.

=VII. LEIOPHYLLAE=

Sheath of the leaf-fascicles deciduous.

Leaves short, erect, the fructification triennial 20. leiophylla.

Leaves long, pendent, the fructification biennial 21. Lumholtzii.

20. PINUS LEIOPHYLLA

1831 P. leiophylla Schlechtendal and Chamisso in Linnaea, vi. 354.

1848 P. chihuahuana Engelmann in Wislizenus, Tour. Mex. 103.

Spring-shoots uninodal. Leaves in fascicles of 3, 4 or 5, the sheath

deciduous, from 8 to 14 cm. long; resin-ducts medial with an occasional

internal duct. Conelets single or verticillate, their scales mucronate;

conelets of the second year only slightly enlarged. Cones maturing the

third year, not exceeding 7 cm. in length, ovate or ovate-conic,

subsymmetrical, more or less reflexed, persistent for several years on

some trees, sometimes serotinous; apophyses lighter or darker brown,

often with an olive or fuscous shade, thin or tumid, the umbo double,

the mucro more persistent near the apex of the cone.

This species grows at subtropical or warm-temperate altitudes in

Mexico, from Oaxaca through the central and western states to southern

Arizona and New Mexico. As it approaches the northern part of its

range the leaves become thicker and more rigid and the number in the

fascicle is reduced to 3 or 4 (var. chihuahuana, Shaw, Pines Mex. 14).

Like P. rigida it sprouts freely along the branches and trunk, and

stumps of felled trees put out shoots in great numbers. The species is

easily recognized by the deciduous sheath and triennial cone.

Plate XVI.

Fig. 151, Branch with fruit of first, second and third years. Fig.

152, Leaf-fascicles. Fig. 153, Magnified leaf-section of the

species. Fig. 154, Magnified leaf-section of the variety.

21. PINUS LUMHOLTZII

1894 P. Lumholtzii Robinson & Fernald in Proc. Am. Acad. xxx. 122.

Spring-shoots uninodal, sometimes multinodal. Leaves in fascicles of 3,

the sheath deciduous, from 20 to 30 cm. long, absolutely pendent;

resin-ducts medial and internal. Conelets subterminal, or lateral and

subterminal, mucronate. Cones not exceeding 7 cm. in length,

symmetrical, pendent on slender peduncles, ovate-conic, early deciduous;

apophyses sublustrous, nut-brown, tumid at the margins, flat on the

surface, the umbo large, the mucro rarely persistent.

A remarkable Pine with long pendent bright green foliage, confined to

the western states of Mexico and ranging on the mountains from

southern Jalisco to the latitude of the city of Chihuahua. Each

season's growth of leaves hangs from the branchlet like a long beard,

from which the tree receives, in some localities, the name "Pino barba

caida." In the herbarium the long leaves, deciduous sheaths, and the

decurrent bases of the bracts, present a combination of characters not

found in other species.

Plate XVI.

Fig. 155, Cone. Fig. 156, Cone. Fig. 157, Leaf-fascicle. Fig. 158,

Magnified leaf-section. Fig. 159, Tree at Ferraria de Tula.

[Illustration: PLATE XVI. P. LEIOPHYLLA (151-154), LUMHOLTZII

(155-159)]

=VIII. LONGIFOLIAE=

Seed-wing adnate to the nut. Leaves long, in fascicles of 3, the sheath

persistent.

Apophysis of the cone prolonged and reflexed 22. longifolia.

Apophysis of the cone low-pyramidal 23. canariensis.

22. PINUS LONGIFOLIA

1803 P. longifolia Roxburgh ex Lambert, Gen. Pin. i. 29, t. 21.

1897 P. Roxburghii Sargent, Silva N. Am. xi. 9.

Spring-shoots uninodal. Leaves in fascicles of 3, the sheath persistent,

from 20 to 30 cm. long; resin-ducts external, the hypoderm often in

large masses, some or all of the endoderm cells with thick outer walls.

Cones from 10 to 17 cm. long, short-pedunculate, ovoid-conic; apophyses

lustrous brown-ochre or fuscous brown, elevated into thick, often

reflexed, beaks with obtuse mutic umbos; seeds with large nuts and

adnate striated dark gray or fuscous brown wings.

Of the three Pines of the Himalayas this species is the most

important. It grows on the outer slopes and foot-hills from Bhotan to

Afghanistan. The wood is used for construction and for the manufacture

of charcoal, the thick soft bark is valuable for tanning, the resin is

abundant and of commercial importance, and the nuts are gathered for

food. The tree is not hardy in cool-temperate climates, but has been

successfully grown in northern Italy.

It differs from P. canariensis in the usually protuberant apophysis of

the cone, in the thick outer walls of the leaf-endoderm and in the

nearly smooth walls of the ray-tracheids of the wood. In the

dimensions of cone and leaf, in the dermal tissues and resin-ducts of

the leaf and in the peculiar coloring of the seed-wing, the two

species are alike.

Plate XVII.

Fig. 160, Cone. Fig. 161, Leaf-fascicle. Fig. 162, Magnified

leaf-section.

23. PINUS CANARIENSIS

1825 P. canariensis Smith in Buch, Canar. Ins. 159.

Spring-shoots uninodal, pruinose. Bud-scales with conspicuously long

free fimbriate margins. Leaves in fascicles of 3, the sheath persistent,

from 20 to 30 cm. long; the hypoderm often in large masses, the

resin-ducts external, the endoderm with thin outer walls. Cones from 10

to 17 cm. long, short-pedunculate, ovoid-conic; apophyses lustrous or

sublustrous nut-brown, more or less pyramidal, the umbo unarmed; seeds

as in the last species.

A species confined to the Canary Islands, but cultivated in northern

Italy. The stately habit of this tree is seen in Schroeter's portrait

(Exc. Canar. Ins. t. 15).

Plate XVII.

Fig. 163, Cone and seed. Fig. 164, Magnified leaf-section. Fig. 165,

Habit of the tree.

[Illustration: PLATE XVII. P. LONGIFOLIA (160-162), CANARIENSIS

(163-165)]

=IX. PINEAE=

Seed-wing articulate, short, ineffective. Leaves binate, the sheath

persistent. One species only.

24. PINUS PINEA

1753 P. pinea Linnaeus, Sp. Pl. 1000.

1778 P. sativa Lamarck, Fl. Franc. ii. 200.

1854 P. maderiensis Tenore in Ann. Sci. Nat. ser. 4, ii. 379.

Spring-shoots uninodal. Leaves from 12 to 20 cm. long; resin-ducts

external. Conelet mutic, slightly larger in the second year. Cones

triennial, from 10 to 14 cm. long, ovoid or subglobose; apophyses

lustrous nut-brown, convex, of large size, the umbo double; seeds large

with a short, loosely articulated, deciduous wing.

A species of the Mediterranean Basin, from Portugal to Syria. Its

northern limit is in southern France and northern Italy, but it is

cultivated in the southern parts of the British Isles and is a

familiar ornament of park and garden in southern Europe, and is valued

for its peculiar beauty and for its large savory nuts. In wood anatomy

as well as in the seed it agrees with the Gerardianae of the Soft

Pines.

Plate XVIII.

Fig. 166, Fruit of three seasons. Fig. 167, Cone-scales and seed.

Fig. 168, Magnified leaf-section. Fig. 169, Habit of the tree.

[Illustration: PLATE XVIII. PINUS PINEA]

=Pinaster=

Bases of the bracts subtending leaf-fascicles decurrent. Seeds with an

effective articulate wing. Umbo of the cone-scales dorsal. Leaves

serrulate, stomatiferous on all faces, the sheath persistent. Walls of

the tracheids of the medullary rays dentate.

Forty-two of the sixty-six species of Pinus are included in this

subsection. As a group they are clearly circumscribed by several

correlated characters and are more closely interrelated than the

twenty-four species previously described. The distinctions of umbo and

seed have disappeared. The umbo here is invariably dorsal, the

seed-wing invariably articulate.

New forms, however, are gradually evolved--the seed with a thick

wing-blade, the indurated oblique cone, the serotinous cone with its

intermittent seed-release, and the multinodal spring-shoot. There are,

moreover, new forms of leaf-hypoderm and a new position of the

resin-duct.

Of these new characters, the thick wing-blade attains such proportions

in the three species of the Macrocarpae that they can be grouped

apart. But the characters that finally culminate in a lateral oblique

serotinous cone are so gradually and irregularly developed that they

offer no divisional distinctions. With the aid of wood and leaf

characters, however, groups can be established which preserve the

evolutionary sequence and, at the same time, the obvious affinity of

the species.

Wing-blade thin or slightly thickened at the base.

Cones dehiscent at maturity.

Pits of the ray-cells large X. Lariciones

Pits of the ray-cells small XI. Australes

Cones serotinous, pits of the ray-cells small XII. Insignes

Wing-blade very thick XIII. Macrocarpae

The species of this subsection are very difficult, if not impossible,

to classify by the usual method, which groups all species under a few

characters assumed to be invariable and of fundamental importance.

Such a method can be successfully applied to the Soft Pines and to

some of the Hard Pines, but cannot be applied to all the Hard Pines

without forcing some of them into unnatural associations.

To take an example, the group Pseudostrobus, characterized by

pentamerous leaf-fascicles, appears in many systems. In this group are

placed P. Torreyana and P. leiophylla. Another group, with trimerous

fascicles, contains P. Sabiniana and P. taeda. Now there are no two

species more obviously related by important peculiarities than P.

Torreyana and P. Sabiniana; nevertheless they are, by this method,

kept apart and associated with species which they resemble in no

important particular.

An attempt is made here to avoid such incongruities. Groups X, XI and

XII represent different stages of evolution. In the Lariciones the

cone is symmetrical, and dehiscent and deciduous at maturity, while

the spring-shoot is uninodal. In the Australes there is a similar

cone, but the spring-shoot gradually becomes multinodal. In the

Insignes the cone is oblique, persistent and serotinous, and the

spring-shoot is multinodal.

These definitions state the degree of evolution attained by each

group, but not all the species of a group conform exactly with its

definition. In each group are species with a characteristic of another

group. Among the Lariciones are a few species with both symmetrical

and oblique cones, and two with persistent cones. Similar exceptions

occur among the Australes. Among the Insignes are a few species with

symmetrical cones, and two with cones that are rarely, if ever,

serotinous.

There is, however, no difficulty in fixing the systematic position of

these exceptional species through other characters which show their

true affinity. They are placed with the species which they most

resemble. Their exceptional characters are merely the evidence of the

evolution that pervades and unites the groups. Therefore the

definition of a group is not necessarily the exact definition of its

species, and a species is placed in a group because all its

characters, specific and evolutional, show a closer affinity with that

group than with the species of any other.

=X. LARICIONES=

Pits of the ray-cells large. Cells of the leaf-hypoderm uniform.

Spring-shoots uninodal. Cones dehiscent at maturity.

This group represents the first stage in the evolution of the Hard

Pines. All the species, like the Soft Pines, are uninodal and the

cones are dehiscent at maturity, but the trend toward the serotinous

species is shown in the occasional appearance of the oblique cone as a

varietal form of a few species, and in the persistent cone of the last

two species of this group.

All the species of this group are of the Old World except P. resinosa

and P. tropicalis. These two are the only American Pines combining

large pits with dentate tracheids, and are the only American Hard

Pines with external resin-ducts of the leaf.

Cones deciduous at maturity.

Cones ovate or ovate-conic.

Conelet with tuberculate or entire scales.

Resin-ducts external and medial 25. resinosa

Resin-ducts septal and external 26. tropicalis

Conelet with mucronate scales.

Resin-ducts mostly external.

Conelet pedunculate, erect.

Cone nut-brown 27. Massoniana

Cone dull tawny yellow 28. densiflora

Conelet pedunculate, reflexed 29. sylvestris

Conelet subsessile, erect 30. montana

Resin-ducts mostly medial.

Bark-formation late 31. luchuensis

Bark-formation early.

Cone nut-brown 32. Thunbergii

Cone lustrous tawny yellow 33. nigra

Cones narrow cylindrical 34. Merkusii

Cones tenaciously persistent.

Leaves stout, relatively short 35. sinensis

Leaves slender, relatively long 36. insularis

25. PINUS RESINOSA

1789 P. resinosa Aiton, Hort. Kew. iii. 367.

1810 P. rubra Michaux f. Hist. Arbr. Am. i. 45, t. 1.

Spring-shoots uninodal. Leaves binate, from 12 to 17 cm. long;

resin-ducts external or external and medial; hypoderm uniform and

inconspicuous. Scales of the conelet mutic. Cones from 4 to 6 cm. long,

subsessile, symmetrical, deciduous the third year, leaving a few basal

scales on the tree; apophyses sublustrous, nut-brown, somewhat thickened

along a transverse keel.

From Nova Scotia and Lake St. John this species ranges westward to the

Winnipeg River and southward into Minnesota, Michigan, northern New

York and eastern Massachusetts, with rare occurrence on the mountains

of Pennsylvania. Under cultivation it is a beautiful tree, adapted to

cold-temperate climates. It was considered by Loiseleur (1812) and by

Spach (1842) to be a variety of P. nigra (laricio). The two species

vary in the color of the cone, the anatomy of the leaves, the buds,

and in the armature of the conelet. A fallen cone of this species is

moreover usually imperfect from the loss of a few basal scales.

Plate XIX.

Fig. 170, Cone and enlarged conelet. Fig. 171, Leaf-fascicle and

magnified leaf-section.

26. PINUS TROPICALIS

1851 P. tropicalis Morelet in Rev. Hort. Cote d'Or, i. 105.

1904 P. terthrocarpa Shaw in Gard. Chron. ser. 3, xxxv. 179, f. 74.

Spring-shoots uninodal. Leaves binate, sometimes ternate, from 15 to 30

cm. long, rigid, erect; hypoderm of uniform thick-walled cells;

resin-ducts of remarkable size, septal, or not quite touching the

endoderm and technically external. Scales of the conelet minutely

tuberculate. Cones from 5 to 8 cm. long, short-pedunculate, erect or

patulous; ovate-conic, symmetrical; apophyses rufous brown,

low-pyramidal, the umbo mutic.

Growing at sea-level within the tropics and confined to western Cuba

and the Isle of Pines. On the island it is associated with P.

caribaea. This species needs no other means of identification than its

peculiar leaf-section. Septal ducts are found in P. oocarpa, Pringlei,

Merkusii and rarely in other species, but they never attain the

extraordinary size that appears to be invariable in P. tropicalis.

Plate XIX.

Fig. 172, Cone and enlarged conelet. Fig. 173, Branch with leaves,

much reduced. Fig. 174, Leaf-fascicle and magnified leaf-section.

Fig. 175, Trees on the Isle of Pines.

[Illustration: PLATE XIX. P. RESINOSA (170, 171), TROPICALIS (172-175)]

27. PINUS MASSONIANA

1803 P. Massoniana Lambert, Gen. Pin. i. 17, t. 12. 1861 P. canaliculata

Miquel in Jour. Bot. Neerland. i. 86.

Spring-shoots uninodal. Leaves binate, rarely ternate, from 12 to 20 cm.

long, slender and pliant; hypoderm inconspicuous; resin-ducts external.

Staminate catkins often in long dense clusters. Conelets partly

tuberculate or mucronate, partly mutic. Cones symmetrical, from 4 to 7

cm. long, ovate-conic, short-pedunculate, early deciduous; apophyses

sublustrous, nut-brown, flat or somewhat elevated, the umbo usually

mutic.

The Chinese Red Pine is found in warm-temperate climates. It is native

to southeastern China and follows the valley of the Yangtse River into

Szech'uan. It has been confused by London with P. pinaster, which it

resembles in no respect, by Siebold with P. Thunbergii, from which it

differs in leaf-dimensions and in leaf-section, and by Mayr with his

P. luchuensis, whose peculiar cortex and whose leaf-section has no

counterpart among Chinese Hard Pines. Its nearest relative is P.

densiflora, from which it differs in its longer leaves, in the color

of its cone and in its conelet (Plate XX, figs. 176, 179).

Plate XX.

Fig. 176, Cone and enlarged conelet. Fig. 177, Two leaf-fascicles.

Fig. 178, Magnified leaf-section.

28. PINUS DENSIFLORA

1842 P. densiflora Siebold & Zuccarini, Fl. Jap. ii. 22, t. 112.

1854 P. scopifera Miquel in Zollinger, Syst. Verz. Ind. Archip. 82.

Spring-shoots more or less pruinose, uninodal. Leaves binate, from 8 to

12 cm. long, slender; hypoderm of few inconspicuous cells; resin-ducts

external. Staminate catkins in long dense clusters. Scales of the

conelet conspicuously mucronate. Cones symmetrical, from 3 to 5 cm.

long, ovate-conic, often persistent for a few years but with a weak hold

on the branch; apophyses dull pale tawny yellow, flat or slightly

elevated, the mucro more or less persistent.

The Japanese Red Pine forms extensive forests on the mountains of

central Japan. It is perfectly hardy in cold-temperate climates. Wild

specimens of China, ascribed to this species, are forms of the

variable P. sinensis. From P. Massoniana it differs in its shorter

leaves and yellow cone, but particularly in the more prominent

prickles and thicker scales of its conelet (figs. 176, 179).

Plate XX.

Fig. 179, Cones and enlarged conelet. Fig. 180, Leaf-fascicles. Fig.

181, Magnified leaf-section and more magnified dermal tissues of the

leaf.

[Illustration: PLATE XX. P. MASSONIANA (176-178), DENSIFLORA (179-181)]

29. PINUS SYLVESTRIS

1753 P. sylvestris Linnaeus, Sp. Pl. 1000 (excl. var.).

1768 P. rubra Miller, Gard. Dict. ed. 8.

1768 P. tatarica Miller, Gard. Dict. ed. 8.

1781 P. mughus Jacquin, Icon. Pl. Rar. i. t. 193 (not Scopoli).

1798 P. resinosa Savi, Fl. Pisa. ii. 354 (not Aiton).

1827 P. humilis Link in Abhandl. Akad. Berlin, 171.

1849 P. Kochiana Klotzsch in Linnaea, xxii. 296.

1849 P. armena Koch in Linnaea, xxii. 297.

1849 P. pontica Koch in Linnaea, xxii. 297.

1859 P. Frieseana Wichura in Flora, xlii. 409.

1906 P. lapponica Mayr, Fremdl. Wald- & Parkb. 348.

Spring-shoots uninodal. Leaves binate, from 3 to 7 cm. long; hypoderm

inconspicuous; resin-ducts external. Conelet reflexed, minutely

mucronate. Cones from 3 to 6 cm. long, reflexed, symmetrical or

sometimes oblique, ovate-conic, deciduous; apophyses dull pale tawny

yellow of a gray or greenish shade, flat, elevated or protuberant and

often much more prominent on the posterior face of the cone, the umbo

with a minute prickle or its remnant.

A tree of great commercial value, with a very extended range, from

Norway, Scotland and southern Spain to northeastern Siberia. A

vigorous hardy species and extensively cultivated. The red upper

trunk, characteristic of this Pine, is not invariable. The dark upper

trunk is sufficiently common to be considered a varietal form

(Mathieu, Flore Forest. ed. 4, 582). In various localities may be

found trees bearing oblique cones, their apophyses showing various

degrees of protuberance up to the extreme development represented in

Loudon's illustration of the variety uncinata (Arb. Brit. iv, f.

2047). This cone is the beginning of the changes that culminate in

species with oblique cones only. In P. sylvestris, however, the

purpose of this form of cone is not apparent except in connection with

this evolution.

Plate XXI.

Figs. 182, 183, Cones. Fig. 184, Leaf-fascicle, magnified

leaf-section and more magnified dermal tissues of the leaf. Fig.

185, Habit of the tree.

30. PINUS MONTANA

1768 P. montana Miller, Gard. Dict. ed. 8.

1772 P. mughus Scopoli, Fl. Carn. ii. 247.

1791 P. pumilio Haenke in Jirasek, Beobacht. 68.

1804 P. mugho Poiret in Lamarck, Encycl. Meth. v. 336.

1805 P. uncinata Ramond ex De Candolle, Lamarck, Fl. Franc. ed. 3,

iii. 726.

1813 P. sanguinea Lapeyrouse, Hist. Pl. Pyren. 587.

1827 P. rotundata Link in Abhandl. Akad. Berlin, 168.

1830 P. obliqua Sauter ex Reichenbach, Fl. Germ. Exc. 159.

1837 P. uliginosa Neumann ex Wimmer, Arb. Schles. Ges. 95.

Spring-shoots uninodal. Leaves binate, from 3 to 8 cm. long, the epiderm

very thick, hypoderm weak; resin-ducts external. Conelets mucronate,

nearly sessile. Cones from 2 to 7 cm. long, subsessile, ovate or

ovate-conic, symmetrical or oblique, often persistent; apophyses

lustrous tawny-yellow or dark brown, both colors often shading into each

other on the same cone, flat, prominent or prolonged into uncinate

beaks of various lengths, the last much more developed on the posterior

face of the cone, the umbo bordered by a narrow dark ring and bearing

the remnant of the mucro.

P. montana grows as a bush or as a small tree, the two forms often

associated. It ranges from central Spain through the Pyrenees, Alps

and Apennines to the Balkan Mountains, associated with P. cembra at

higher, with P. sylvestris at lower altitudes. It grows indifferently

in bogs and on rocky slopes. Its dwarf form, under the name of the

Mugho Pine, is extensively cultivated as a garden ornament.

On the differences of the cone this species has been divided into

three subspecies: uncinata, with an oblique cone and protuberant

apophyses; pumilio, with a symmetrical cone and an excentric umbo;

mughus, with a symmetrical cone and a concentric umbo. Other

segregations based on the degree of development of the apophysis and

on the size and color of the cone, have received names of four or even

five terms--Pinus montana pumilio applanata--or Pinus montana uncinata

rostrata castanea etc., etc. These elaborations may be seen in the

Tharand Jahrbuch of 1861, p. 166, and with them appear also Hartig's

specifications of 60 forms of this species, each dignified with a

Latin name.

Plate XXI.

Fig. 186, Cone of var. uncinata. Figs. 187, 188, Cones. Fig. 189,

Leaf-fascicles, magnified leaf-section and more magnified dermal

tissues of the leaf. Fig. 190, Tree and dwarf-form of the Pyrenees.

[Illustration: PLATE XXI. P. SYLVESTRIS (182-185), MONTANA (186-190)]

31. PINUS LUCHUENSIS

1894 P. luchuensis Mayr in Bot. Centralbl. lviii. 149, f.

Spring-shoots uninodal. Bark-formation late, the upper trunk covered

with a smooth cortex. Leaves binate, from 12 to 16 cm. long, the epiderm

thick, hypoderm of two or three rows of cells; resin-ducts medial or

with an occasional external duct. Conelets mucronate toward the apex.

Cones from 3 to 6 cm. long, ovate-conic, symmetrical; apophyses lustrous

nut-brown, transversely carinate, the umbo unarmed.

This Pine is known to me through Mayr's description and a single dried

specimen. The smooth cortex of young trees distinguishes it from all

other east-Asiatic Hard Pines. Mayr includes under this species the

Pine of Hong Kong. But in this he must be mistaken, for there is no

species yet found in China that agrees with the description of P.

luchuensis.

Plate XXII.

Fig. 191, Cone. Fig. 192, Leaf-fascicle and magnified leaf-section.

32. PINUS THUNBERGII

1784 P. sylvestris Thunberg, Fl. Jap. 274 (not Linnaeus).

1842 P. Massoniana Siebold & Zuccarini. Fl. Jap. ii. 24, t. 113

(not Lambert).

1868 P. Thunbergii Parlatore in DC. Prodr. xvi-2, 388.

Spring-shoots uninodal. Buds of leading-shoots white and conspicuous.

Leaves binate, from 6 to 11 cm. long, the epiderm thick, hypoderm

strong, resin-ducts medial. Conelets with short-mucronate scales. Cones

from 4 to 6 cm. long, ovate or ovate-conic, symmetrical; apophyses

nut-brown, flat or convex and transversely carinate, the prickle of the

umbo more or less persistent.

The Black Pine of Japan has been cultivated for centuries, and by

skillful Japanese gardeners has been trained into dwarf and other

curious forms. It is hardy in cold-temperate climates. It is distinct

from P. densiflora by the medial ducts of its leaf, from P. nigra by

the fewer, larger, brown scales of its cone, and from P. resinosa by

the armature of its conelet. It appears in most determinations of

Chinese collections, but there is no Chinese Pine with the white buds

and the medial leaf-ducts of this species.

Plate XXII.

Fig. 196, Two cones. Fig. 197, Leaf-fascicle and magnified

leaf-section.

33. PINUS NIGRA

1785 P. nigra Arnold, Reise n. Mariaz. 8, t.

1804 P. laricio Poiret in Lamarck, Encycl. Meth. v. 339.

1808 P. halepensis Bieberstein, Fl. Taur. Cauc. ii. 408 (not Miller).

1809 P. pinaster Besser, Fl. Galic. ii. 294 (not Aiton).

1813 P. maritima Aiton, f. Hort. Kew. v. 315 (not Lambert).

1816 P. sylvestris Baumgarten, Stirp. Transsilv. ii. 304

(not Linnaeus).

1818 P. pyrenaica Lapeyrouse, Hist. Pl. Pyren. Suppl. 146.

1824 P. Pallasiana Lambert, Gen. Pin. ii. 1, t. 1.

1825 P. austriaca Hoess in Flora, viii-1, Beil. 113.

1831 P. nigricans Host, Fl. Austr. ii. 628.

1842 P. dalmatica Visiani, Fl. Dalmal. 199, note.

1851 P. Salzmanni Dunal in Mem. Acad. Montp. ii. 82, tt.

1863 P. Heldreichii Christ in Verh. Nat. Ges. Basel, iii. 549.

1864 P. leucodermis Antoine in Oesterr. Bot. Zeitschr. xiv. 366.

1896 P. pindica Formanek in Verh. Nat. Ver. Bruenn, xxxiv. 272.

Spring-shoots uninodal. Leaves binate, from 9 to 16 cm. long, the

epiderm thick, hypoderm conspicuous, resin-ducts medial. Conelets

mucronate. Cones from 4 to 8 cm. long, subsessile, symmetrical;

apophyses lustrous, tawny yellow, transversely carinate, the keel

strongly convex, the mucro of the umbo more or less persistent.

A valuable tree unequally distributed over the mountain slopes of

central and southern Europe and Asia Minor. The typical form, under

the name of the Austrian Pine, is a familiar exotic of the Middle and

Eastern States of America. As Mathieu states (Flore Forest., ed. 4,

597), this species is quite constant in cone and bark. It may be added

that the anatomy of the leaf is also constant, while the dimensions of

both leaf and cone present no unusual variations. The varieties

generally accepted are founded on the habit of the tree, a character

of forestal or horticultural rather than of botanical importance.

Plate XXII.

Fig. 193, Two cones. Fig. 194, Leaf-fascicle and magnified

leaf-section. Fig. 195, Magnified dermal tissues of the leaf.

[Illustration: PLATE XXII. P. LUCHUENSIS (191, 192), NIGRA (193-195),

THUNBERGII (196, 197)]

34. PINUS MERKUSII

1790 P. sylvestris Loureiro, Fl. Cochinch. ii. 579 (not Linnaeus).

1845 P. Merkusii De Vriese, Pl. Nov. Ind. Bat. 5, t. 2.

1847 P. Finlaysoniana Wallich ex Blume, Rumphia, iii. 210.

1849 P. Latteri Mason in Jour. Asiat. Soc. i. 74.

Spring-shoots uninodal. Leaves binate, slender, from 15 to 20 cm. long,

the hypoderm of uniform thick-walled cells, resin-ducts medial, or with

internal or septal ducts, endoderm-cells very unequal in size, some of

them large. Conelets unarmed. Cones from 5 to 8 cm. long, peculiarly

narrow-cylindrical, symmetrical; apophyses lustrous, rufous brown,

radially carinate, the transverse keel prominent.

Of the habit of this Pine I know nothing. As a species it is very

clearly defined by its peculiar cone and leaf-section. It grows in the

Philippines, Sumatra, Lower Burmah and western Indo-China. In my

specimen the pits of the ray-cells of the wood are both large and

small. In this particular it may belong in either of two groups of

species. Its uniform leaf-hypoderm associates it with this group or

with P. halepensis of the Insignes. I have assumed the cone to be

dehiscent at maturity and have placed it with the Lariciones, but if

further information shows the cone to be serotinous, this species

should be transferred to the serotinous group.

Plate XXIII.

Fig. 198, Cone. Fig. 199, Magnified sections of two leaves. Fig.

200, Leaf-fascicle.

35. PINUS SINENSIS

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