[1] See further under SCYPHOMEDUSAE.
HYENA, a name applicable to all the representatives of the mammalian
family _Hyaenidae_, a group of Carnivora (q.v.) allied to the civets.
From all other large Carnivora except the African hunting-dog, hyenas
are distinguished by having only four toes on each foot, and are further
characterized by the length of the fore-legs as compared with the hind
pair, the non-retractile claws, and the enormous strength of the jaws
and teeth, which enables them to break the hardest bones and to retain
what they have seized with unrelaxing grip.
[Illustration: FIG. 1.--The Striped Hyena (_Hyaena striata_).]
[Illustration: FIG. 2.--The Spotted Hyena (_Hyaena crocuta_).]
The striped hyena (_Hyaena striata_) is the most widely distributed
species, being found throughout India, Persia, Asia Minor, and North and
East Africa, the East African form constituting a distinct race, _H.
striata schillingsi_; while there are also several distinct Asiatic
races. The species resembles a wolf in size, and is greyish-brown In
colour, marked with indistinct longitudinal stripes of a darker hue,
while the legs are transversely striped. The hairs on the body are long,
especially on the ridge of the neck and back, where they form a distinct
mane, which is continued along the tail. Nocturnal in habits, it prefers
by day the gloom of caves and ruins, or of the burrows which it
occasionally forms, and issues forth at sunset, when it commences its
unearthly howling. When the animal is excited, the howl changes into
what has been compared to demoniac laughter, whence the name of
"laughing-hyena." These creatures feed chiefly on carrion, and thus
perform useful service by devouring remains which might otherwise
pollute the air. Even human dead are not safe from their attacks, their
powerful claws enabling them to gain access to newly interred bodies in
cemeteries. Occasionally (writes Dr W. T. Blanford) sheep or goats, and
more often dogs, are carried off, and the latter, at all events, are
often taken alive to the animal's den. This species appears to be
solitary in habits, and it is rare to meet with more than two together.
The cowardice of this hyena is proverbial; despite its powerful teeth,
it rarely attempts to defend itself. A very different animal is the
spotted hyena, _Hyaena (Crocuta) crocuta_, which has the sectorial teeth
of a more cat-like type, and is marked by dark-brown spots on a
yellowish ground, while the mane is much less distinct. At the Cape it
was formerly common, and occasionally committed great havoc among the
cattle, while it did not hesitate to enter the Kaffir dwellings at
night and carry off children sleeping by their mothers. By persistent
trapping and shooting, its numbers have now been considerably reduced,
with the result, however, of making it exceedingly wary, so that it is
not readily caught in any trap with which it has had an opportunity of
becoming acquainted. Its range extends from Abyssinia to the Cape. The
Abyssinian form has been regarded as a distinct species, under the name
of _H. liontiewi_, but this, like various more southern forms, is but
regarded as a local race. The brown hyena (_H. brunnea_) is South
African, ranging to Angola on the west and Kilimanjaro on the east. In
size it resembles the striped hyena, but differs in appearance, owing to
the fringe of long hair covering the neck and fore part of the back. The
general hue is ashy-brown, with the hair lighter on the neck (forming a
collar), chest and belly; while the legs are banded with dark brown.
This species is not often seen, as it remains concealed during the day.
Those frequenting the coast feed on dead fish, crabs and an occasional
stranded whale, though they are also a danger to the sheep and cattle
kraal. Strand-wolf is the local name at the Cape.
Although hyenas are now confined to the warmer regions of the Old World,
fossil remains show that they had a more northerly range during Tertiary
times; the European cave-hyena being a form of the spotted species,
known as _H. crocuta spelaea_. Fossil hyenas occur in the Lower Pliocene
of Greece, China, India, &c.; while remains indistinguishable from those
of the striped species have been found in the Upper Pliocene of England
and Italy.
HYÈRES, a town in the department of the Var in S.E. France, 11 m. by
rail E. of Toulon. In 1906 the population of the commune was 17,790, of
the town 10,464; the population of the former was more than doubled in
the last decade of the 19th century. Hyères is celebrated (as is also
its fashionable suburb, Costebelle, nearer the seashore) as a winter
health resort. The town proper is situated about 2½ m. from the
seashore, and on the south-western slope of a steep hill (669 ft.,
belonging to the Maurettes chain, 961 ft.), which is one of the
westernmost spurs of the thickly wooded Montagnes des Maures. It is
sheltered from the north-east and east winds, but is exposed to the cold
north-west wind or _mistral_. Towards the south and south-east a fertile
plain, once famous for its orange groves, but now mainly covered by
vineyards and farms, stretches to the sea, while to the south-west,
across a narrow valley, rises a cluster of low hills, on which is the
suburb of Costebelle. The older portion of the town is still surrounded,
on the north and east, by its ancient, though dilapidated medieval
walls, and is a labyrinth of steep and dirty streets. The more modern
quarter which has grown up at the southern foot of the hill has handsome
broad boulevards and villas, many of them with beautiful gardens, filled
with semi-tropical plants. Among the objects of interest in the old town
are: the house (Rue Rabaton, 7) where J. B. Massillon (1663-1742), the
famous pulpit orator, was born; the parish church of St Louis, built
originally in the 13th century by the Cordelier or Franciscan friars,
but completely restored in the earlier part of the 19th century; and the
site of the old château, on the summit of the hill, now occupied by a
villa. The plain between the new town and the sea is occupied by large
nurseries, an excellent _jardin d'acclimatation_, and many market
gardens, which supply Paris and London with early fruits and vegetables,
especially artichokes, as well as with roses in winter. There are
extensive salt beds (_salines_) both on the peninsula of Giens, S. of
the town, and also E. of the town. To the east of the Giens peninsula is
the fine natural harbour of Hyères, as well as three thinly populated
islands (the Stoechades of the ancients), Porquerolles, Port Cros and Le
Levant, which are grouped together under the common name of Îles
d'Hyères.
The town of Hyères seems to have been founded in the 10th century, as a
place of defence against pirates, and takes its name from the aires
(_hierbo_ in the Provençal dialect), or threshing-floors for corn, which
then occupied its site. It passed from the possession of the viscounts
of Marseilles to Charles of Anjou, count of Provence, and brother of St
Louis (the latter landed here in 1254, on his return from Egypt). The
château was dismantled by Henri IV., but thanks to its walls, the town
resisted in 1707 an attack made by the duke of Savoy.
See Ch. Lenthéric, _La Provence Maritime ancienne et moderne_ (chap.
5) (Paris, 1880). (W. A. B. C.)
HYGIEIA, in Greek mythology, the goddess of health. It seems probable
that she was originally an abstraction, subsequently personified, rather
than an independent divinity of very ancient date. The question of the
original home of her worship has been much discussed. The oldest traces
of it, so far as is known at present, are to be found at Titane in the
territory of Sicyon, where she was worshipped together with Asclepius,
to whom she appears completely assimilated, not an independent
personality. Her cult was not introduced at Epidaurus till a late date,
and therefore, when in 420 B.C. the worship of Asclepius was introduced
at Athens coupled with that of Hygieia, it is not to be inferred that
she accompanied him from Epidaurus, or that she is a Peloponnesian
importation at all. It is most probable that she was invented at the
time of the introduction of Asclepius, after the sufferings caused by
the plague had directed special attention to sanitary matters. The
already existing worship of Athena Hygieia had nothing to do with
Hygieia the goddess of health, but merely denoted the recognition of the
power of healing as one of the attributes of Athena, which gradually
became crystallized into a concrete personality. At first no special
relationship existed between Asclepius and Hygieia, but gradually she
came to be regarded as his daughter, the place of his wife being already
secured by Epione. Later Orphic hymns, however, and Herodas iv. 1-9,
make her the wife of Asclepius. The cult of Hygieia then spread
concurrently with that of Asclepius, and was introduced at Rome from
Epidaurus in 293, by which time she may have been admitted (which was
not the case before) into the Epidaurian family of the god. Her proper
name as a Romanized Greek importation was Valetudo, but she was
gradually identified with Salus, an older genuine Italian divinity, to
whom a temple had already been erected in 302. While in classical times
Asclepius and Hygieia are simply the god and goddess of health, in the
declining years of paganism they are protecting divinities generally,
who preserve mankind not only from sickness but from all dangers on land
and sea. In works of art Hygieia is represented, together with
Asclepius, as a maiden of benevolent appearance, wearing the chiton and
giving food or drink to a serpent out of a dish.
See the article by H. Lechat in Daremberg and Saglio's _Dictionnaire
des antiquités_, with full references to authorities; and E. Thrämer
in Roscher's _Lexikon der Mythologie_, with a special section on the
modern theories of Hygieia.
HYGIENE (Fr. _hygiène_, from Gr. [Greek: hygiainein], to be healthy),
the science of preserving health, its practical aim being to render
"growth more perfect, decay less rapid, life more vigorous, death more
remote." The subject is thus a very wide one, embracing all the agencies
which affect the physical and mental well-being of man, and it requires
acquaintance with such diverse sciences as physics, chemistry, geology,
engineering, architecture, meteorology, epidemiology, bacteriology and
statistics. On the personal or individual side it involves consideration
of the character and quality of food and of water and other beverages;
of clothing; of work, exercise and sleep; of personal cleanliness, of
special habits, such as the use of tobacco, narcotics, &c.; and of
control of sexual and other passions. In its more general and public
aspects it must take cognizance of meteorological conditions, roughly
included under the term climate; of the site or soil on which dwellings
are placed; of the character, materials and arrangement of dwellings,
whether regarded individually or in relation to other houses among which
they stand; of their heating and ventilation; of the removal of excreta
and other effete matters; of medical knowledge relating to the incidence
and prevention of disease; and of the disposal of the dead.
These topics will be found treated in such articles as DIETETICS,
FOOD, FOOD-PRESERVATION, ADULTERATION, WATER, HEATING, VENTILATION,
SEWERAGE, BACTERIOLOGY, HOUSING, CREMATION, &c. For legal enactments
which concern the sanitary well-being of the community, see PUBLIC
HEALTH.
HYGINUS, eighth pope. It was during his pontificate (c. 137-140) that
the gnostic heresies began to manifest themselves at Rome.
HYGINUS (surnamed GROMATICUS, from _gruma_, a surveyor's measuring-rod),
Latin writer on land-surveying, flourished in the reign of Trajan (A.D.
98-117). Fragments of a work on legal boundaries attributed to him will
be found in C. F. Lachmann, _Gromatici Veteres_, i. (1848).
A treatise on Castrametation (_De Munitionibus Castrorum_), also
attributed to him, is probably of later date, about the 3rd century
A.D. (ed. W. Gemoll, 1879; A. von Domaszewski, 1887).
HYGINUS, GAIUS JULIUS, Latin author, a native of Spain (or Alexandria),
was a pupil of the famous Cornelius Alexander Polyhistor and a freedman
of Augustus, by whom he was made superintendent of the Palatine library
(Suetonius, _De Grammaticis_, 20). He is said to have fallen into great
poverty in his old age, and to have been supported by the historian
Clodius Licinus. He was a voluminous author, and his works included
topographical and biographical treatises, commentaries on Helvius Cinna
and the poems of Virgil, and disquisitions on agriculture and
bee-keeping. All these are lost.
Under the name of Hyginus two school treatises on mythology are
extant: (1) _Fabularum Liber_, some 300 mythological legends and
celestial genealogies, valuable for the use made by the author of the
works of Greek tragedians now lost; (2) _De Astronomia_, usually
called _Poetica Astronomica_, containing an elementary treatise on
astronomy and the myths connected with the stars, chiefly based on the
[Greek: Katasterismoi] of Eratosthenes. Both are abridgments and both
are by the same hand; but the style and Latinity and the elementary
mistakes (especially in the rendering of the Greek originals) are held
to prove that they cannot have been the work of so distinguished a
scholar as C. Julius Hyginus. It is suggested that these treatises are
an abridgment (made in the latter half of the 2nd century) of the
_Genealogiae_ of Hyginus by an unknown grammarian, who added a
complete treatise on mythology.
EDITIONS.--_Fabulae_, by M. Schmidt (1872); _De Astronomia_, by B.
Bunte (1875); see also Bunte, _De C. Julii Hygini, Augusti Liberti,
Vita et Scriptis_ (1846).
HYGROMETER (Gr. [Greek: hygros], moist, [Greek: metron], a measure), an
instrument for measuring the absolute or relative amount of moisture in
the atmosphere; an instrument which only qualitatively determines
changes in the humidity is termed a "hygroscope." The earlier
instruments generally depended for their action on the contraction or
extension of substances when exposed to varying degrees of moisture;
catgut, hair, twisted cords and wooden laths, all of which contract with
an increase in the humidity and vice versa, being the most favoured
materials. The familiar "weather house" exemplifies this property. This
toy consists of a house provided with two doors, through which either a
man or woman appears according as the weather is about to be wet or
fine. This action is effected by fixing a catgut thread to the base on
which the figures are mounted, in such a manner that contraction of the
thread rotates the figures so that the man appears and extension so that
the woman appears.
Many of the early forms are described in C. Hutton, _Math. and Phil.
Dictionary_ (1815). The modern instruments, which utilize other
principles, are described in METEOROLOGY: II. _Methods and Apparatus_.
HYKSOS, or "SHEPHERD KINGS," the name of the earliest invaders of Egypt
of whom we have definite evidence in tradition. Josephus (c. _Apion._ i.
14), who identifies the Hyksos with the Israelites, preserves a passage
from the second book of Manetho giving an account of them. (It may be
that Josephus had it, not direct from Manetho's writings, but through
the garbled version of some Alexandrine compiler.) In outline it is as
follows. In the days of a king of Egypt named Timaeus the land was
suddenly invaded from the east by men of ignoble race, who conquered it
without a struggle, destroyed cities and temples, and slew or enslaved
the inhabitants. At length they elected a king named Salatis, who,
residing at Memphis, made all Egypt tributary, and established garrisons
in different parts, especially eastwards, fearing the Assyrians. He
built also a great fortress at Avaris, in the Sethroite nome, east of
the Bubastite branch of the Nile. Salatis was followed in succession by
Beon, Apachnas, Apophis, Jannas and Asses. These six kings reigned 198
years and 10 months, and all aimed at extirpating the Egyptians. Their
whole race was named Hyksos, i.e. "shepherd kings," and some say they
were Arabs (another explanation found by Josephus is "captive
shepherds"). When they and their successors had held Egypt for 511
years, the kings of the Thebais and other parts of Egypt rebelled, and a
long and mighty war began. Misphragmuthosis worsted the "Shepherds" and
shut them up in Avaris; and his son Thutmosis, failing to capture the
stronghold, allowed them to depart; whereupon they went forth, 240,000
in number, established themselves in Judea and built Jerusalem.
In Manetho's list of kings, the six above named (with many variations in
detail) form the XVth dynasty, and are called "six foreign Phoenician
kings." The XVIth dynasty is of thirty-two "Hellenic (_sic?_) shepherd
kings," the seventeenth is of "shepherds and Theban kings" (reigning
simultaneously). The lists vary greatly in different versions, but the
above seems the most reasonable selection of readings to be made. For
"Hellenic" see below. The supposed connexion with the Israelites has
made the problem of the Hyksos attractive, but light is coming upon it
very slowly. In 1847 E. de Rougé proved from a fragment of a story in
the papyri of the British Museum, that Apopi was one of the latest of
the Hyksos kings, corresponding to Aphobis; he was king of the "pest"
and suppressed the worship of the Egyptian gods, and endeavoured to make
the Egyptians worship his god Setekh or Seti; at the same time an
Egyptian named Seqenenre reigned in Thebes, more or less subject to
Aphobis. The city of Hawari (Avaris) was also mentioned in the fragment.
In 1850 a record of the capture of this city from the Hyksos by Ahmosi,
the founder of the eighteenth dynasty, was discovered by the same
scholar. A large class of monuments was afterwards attributed to the
Hyksos, probably in error. Some statues and sphinxes, found in 1861 by
Mariette at Tanis (in the north-east of the Delta), which had been
usurped by later kings, had peculiar "un-Egyptian" features. One of
these bore the name of Apopi engraved lightly on the shoulder; this was
evidently a usurper's mark, but from the whole circumstances it was
concluded that these, and others of the same type of features found
elsewhere, must have belonged to the Hyksos. This view held the field
until 1893, when Golénischeff produced an inferior example bearing its
original name, which showed that in this case it represented Amenemhe
III. In consequence it is now generally believed that they all belong to
the twelfth dynasty. Meanwhile a headless statue of a king named Khyan,
found at Bubastis, was attributed on various grounds to the Hyksos, the
soundest arguments being his foreign name and the boastful un-Egyptian
epithet "beloved of his _ka_," where "beloved of Ptah" or some other god
was to be expected. His name was immediately afterwards recognized on a
lion found as far away from Egypt as Bagdad. Flinders Petrie then
pointed out a group of kings named on scarabs of peculiar type, which,
including Khyan, he attributed to the period between the Old Kingdom and
the New, while others were in favour of assigning them all to the
Hyksos, whose appellation seemed to be recognizable in the title
Hek-khos, "ruler of the barbarians," borne by Khyan. The extraordinary
importance of Khyan was further shown by the discovery of his name on a
jar-lid at Cnossus in Crete. Semitic features were pointed out in the
supposed Hyksos names, and Petrie was convinced of their date by his
excavations of 1905-1906 in the eastern Delta. Avaris is generally
assigned to the region towards Pelusium on the strength of its being
located in the Sethroite nome by Josephus, but Petrie thinks it was at
Tell el-Yahudiyeh (Yehudia), where Hyksos scarabs are common. From the
remains of fortifications there he argues that the Hyksos were
uncivilized desert people, skilled in the use of the bow, and must thus
have destroyed by their archery the Egyptian armies trained to fight
hand-to-hand; further, that their hordes were centered in Syria, but
were driven thence by a superior force in the East to take refuge in the
islands and became a sea-power--whence the strange description
"Hellenic" in Manetho, which most editors have corrected to [Greek:
alloi], "others." Besides the statue of Khyan, blocks of granite with
the name of Apopi have been found in Upper Egypt at Gebelen and in
Lower Egypt at Bubastis. The celebrated Rhind mathematical papyrus was
copied in the reign of an Apopi from an original of the time of Amenemhe
III. Large numbers of Hyksos scarabs are found in Upper and Lower Egypt,
and they are not unknown in Palestine. Khyan's monuments, inconspicuous
as they are, actually extend over a wider area--from Bagdad to
Cnossus--than those of any other Egyptian king.
It is certain that this mysterious people were Asiatic, for they are
called so by the Egyptians. Though Seth was an Egyptian god, as god of
the Hyksos he represents some Asiatic deity. The possibility of a
connexion between the Hyksos and the Israelites is still admitted in
some quarters. Hatred of these impious foreigners, of which there is
some trace in more than one text, aroused amongst the Egyptians (as
nothing ever did before or since) that martial spirit which carried the
armies of Tethmosis to the Euphrates.
Besides the histories of Egypt, see J. H. Breasted, _Ancient Records
of Egypt_; Historical Documents ii. 4, 125; G. Maspero, _Contes
populaires_, 3me éd. p. 236; W. M. F. Petrie, _Hyksos and Israelite
Cities_, p. 67; Golénischeff in _Recueil de travaux_, xv. p. 131.
(F. Ll. G.)
HYLAS, In Greek legend, son of Theiodamas, king of the Dryopians in
Thessaly, the favourite of Heracles and his companion on the Argonautic
expedition. Having gone ashore at Kios in Mysia to fetch water, he was
carried off by the nymphs of the spring in which he dipped his pitcher.
Heracles sought him in vain, and the answer of Hylas to his
thrice-repeated cry was lost in the depths of the water. Ever
afterwards, in memory of the threat of Heracles to ravage the land if
Hylas were not found, the inhabitants of Kios every year on a stated day
roamed the mountains, shouting aloud for Hylas (Apollonius Rhodius i.
1207; Theocritus xiii.; Strabo xii. 564; Propertius i. 20; Virgil,
_Ecl._ vi. 43). But, although the legend is first told in Alexandrian
times, the "cry of Hylas" occurs long before as the "Mysian cry" in
Aeschylus (_Persae_, 1054), and in Aristophanes (_Plutus_, 1127) "to cry
Hylas" is used proverbially of seeking something in vain. Hylas, like
Adonis and Hyacinthus, represents the fresh vegetation of spring, or the
water of a fountain, which dries up under the heat of summer. It is
suggested that Hylas was a harvest deity and that the ceremony gone
through by the Kians was a harvest festival, at which the figure of a
boy was thrown into the water, signifying the dying vegetation-spirit of
the year.
See G. Türk in _Breslauer Philologische Abhandlungen_, vii. (1895); W.
Mannhardt, _Mythologische Forschungen_ (1884).
HYLOZOISM (Gr. [Greek: hylê], matter, [Greek: zôê], life), in
philosophy, a term applied to any system which explains all life,
whether physical or mental, as ultimately derived from matter ("cosmic
matter," _Weldstoff_). Such a view of existence has been common
throughout the history of thought, and especially among physical
scientists. Thus the Ionian school of philosophy, which began with
Thales, sought for the beginning of all things in various material
substances, water, air, fire (see IONIAN SCHOOL). These substances were
regarded as being in some sense alive, and taking some active part in
the development of being. This primitive hylozoism reappeared in
modified forms in medieval and Renaissance thought, and in modern times
the doctrine of materialistic monism is its representative. Between
modern materialism and hylozoism proper there is, however, the
distinction that the ancients, however vaguely, conceived the elemental
matter as being in some sense animate if not actually conscious and
conative.
HYMEN, or HYMENAEUS, originally the name of the song sung at marriages
among the Greeks. As usual the name gradually produced the idea of an
actual person whose adventures gave rise to the custom of this song. He
occurs often in association with Linus and Ialemus, who represent
similar personifications, and is generally called a son of Apollo and a
Muse. As the son of Dionysus and Aphrodite, he was regarded as a god of
fruitfulness. In Attic legend he was a beautiful youth who, being in
love with a girl, followed her in a procession to Eleusis disguised as a
woman, and saved the whole band from pirates. As reward he obtained the
girl in marriage, and his happy married life caused him ever afterwards
to be invoked in marriage songs (Servius on Virgil, _Aen._ i. 651).
According to another story, he was a youth who was killed by the fall of
his house on his wedding day; hence he was invoked, to propitiate him
and avert a similar fate from others (Servius, loc. cit.). He is
represented in works of art as an effeminate-looking, winged youth,
carrying a bridal torch and wearing a nuptial veil. The marriage song
was sung, with musical accompaniment, during the procession of the bride
from her parents' house to that of the bridegroom, Hymenaeus being
invoked at the end of each portion.
See R. Schmidt, _De Hymenaeo el Talasio_ (1886), and J. A. Hild in
Daremberg and Saglis's _Dictionnaire des antiquités_.
HYMENOPTERA (Gr. [Greek: hymên], a membrane, and [Greek: pteron], a
wing), a term used in zoological classification for one of the most
important orders of the class _Hexapoda_ (q.v.). The order was founded
by Linnaeus (_Systema Naturae_, 1735), and is still recognized by all
naturalists in the sense proposed by him, to include the saw-flies,
gall-flies, ichneumon-flies and their allies, ants, wasps and bees. The
relationship of the Hymenoptera to other orders of insects is discussed
in the article HEXAPODA, but it may be mentioned here that in structure
the highest members of the order are remarkably specialized, and that in
the perfection of their instincts they stand at the head of all insects
and indeed of all invertebrate animals. About 30,000 species of
Hymenoptera are now known.
[Illustration: After C. L. Marlatt, _Bur. Ent. Bull. 3, N.S., U.S. Dept.
Agric._
FIG. 1.--A, Front of head of Saw-fly (_Pachynematus_); a, labrum; b,
clypeus; c, vertex; d, d, antennal cavities. C and D, Mandibles. E,
First maxilla; a, cardo; b, stipes; c, galea; d, lacinia; e, palp. B,
Second maxillae (Labium); a, mentum; b, ligula (between the two galeae);
c, c, palps. Magnified.]
[Illustration: FIG. 2.--Jaws of Hive-bee (_Apis mellifica_). Magnified
about 6½ times. a, mandible; b, c, palp and lacinia of first maxilla; d,
e, g, h, mentum, palp, fused laciniae (ligula or "tongue") and galea of
2nd maxillae.]
[Illustration: After C. Janet, _Mem. Soc. Zool. France_ (1898).
FIG. 3.--Median section through mid-body of female Red Ant (_Myrmica
rubra_). H, Head; 1, 2, 3, the thoracic segments; i., ii., the first and
second abdominal segments; i., being the propodeum.]
_Characters._--In all Hymenoptera the mandibles (fig. 1, C, D) are
well developed, being adapted, as in the more lowly winged insects,
such as the Orthoptera, for biting. The more generalized Hymenoptera
have the second maxillae but slightly modified, their inner lobes
being fused to form a _ligula_ (fig. 1, B, b). In the higher families
this structure becomes elongated (fig. 2, g) so as to form an
elaborate sucking-organ or "tongue." These insects are able,
therefore, to bite as well as to suck, whereas most insects which have
acquired the power of suction have lost that of biting. Both fore- and
hind-wings are usually present, both pairs being membranous, the
hind-wings small and not folded when at rest, each provided along the
costa with a row of curved hooks which catch on to a fold along the
dorsum of the adjacent fore-wing during flight. A large number of
Hymenoptera are, however, entirely wingless--at least as regards one
sex or form of the species. One of the most remarkable features is the
close union of the foremost abdominal segment (fig. 3, i.) with the
metathorax, of which it often seems to form a part, the apparent first
abdominal segment being, in such case, really the second (fig. 3,
ii.). The true first segment, which undergoes a more or less complete
fusion with the thorax is known as the "median segment" or
_propodeum_. In female Hymenoptera the typical insectan ovipositor
with its three pairs of processes is well developed, and in the higher
families this organ becomes functional as a sting (fig. 5),--used for
offence and defence. As regards their life history, all Hymenoptera
undergo a "complete" metamorphosis. The larva is soft-skinned
(eruciform), being either a caterpillar (fig. 6, b) or a legless grub
(fig. 7, a), and the pupa is free (fig. 7, c), i.e. with the
appendages not fixed to the body, as is the case in the pupa of most
moths.
[Illustration: FIG. 4.--Fore-Wings of Hymenoptera.
1. Tenthredinidae (_Hylotoma_)-- 1, marginal; 2, appendicular; 3, 4,
5, 6, radial or submarginal; 7, 8, 9, median or discoidal; 10,
sub-costal; 11, 12, cubital or branchial; and 13, anal or lanceolate
cellules; a, b, c, submarginal nervures; d, basal nervures; e, f,
recurrent nervures; st, stigma; co, costa.
2. Cynipidae (_Cynips_).
3. Chalcididae (_Perilampus_).
4. Proctotrypidae (_Codrus_).
5. Mymaridae (_Mymar_).
6. Braconidae (_Bracon_).
7. Ichneumonidae (_Trogus_).
8. Chrysididae (_Cleptes_).
9. Formicidae (_Formica_).
10. Vespidae (_Vespa_).
11. Apidae (_Apathus_).]
_Structure._--The head of a hymenopterous insect bears three simple
eyes (ocelli) on the front and vertex in addition to the large
compound eyes. The feelers are generally simple in type, rarely
showing serrations or prominent appendages; but one or two basal
segments are frequently differentiated to form an elongate "scape,"
the remaining segments--carried at an elbowed angle to the
scape--making up the "flagellum"; the segments of the flagellum often
bear complex sensory organs. The general characters of the jaws have
been mentioned above, and in detail there is great variation in these
organs among the different families. The sucking tongue of the
Hymenoptera has often been compared with the hypopharynx of other
insects. According to D. Sharp, however, the hypopharynx is present in
all Hymenoptera as a distinct structure at the base of the "tongue,"
which must be regarded as representing the fused laciniae of the
second maxillae. In the thorax the pronotum and prosternum are closely
associated with the mesothorax, but the pleura of the prothorax are
usually shifted far forwards, so that the fore-legs are inserted just
behind the head. A pair of small plates--the tegulae--are very
generally present at the bases of the fore-wings. The union of the
first abdominal segment with the metathorax has been already
mentioned. The second (so-called "first") abdominal segment is often
very constricted, forming the "waist" so characteristic of wasps and
ants for example. The constriction of this segment and its very
perfect articulation with the propodeum give great mobility to the
abdomen, so that the ovipositor or sting can be used with the greatest
possible accuracy and effect.
Mention has already been made of the series of curved hooks along the
costa of the hind-wing; by means of this arrangement the two wings of
a side are firmly joined together during flight, which thus becomes
particularly accurate. The wings in the Hymenoptera show a marked
reduction in the number of nervures as compared with more primitive
insects. The main median nervure, and usually also the sub-costal
become united with the radial, while the branches of radial, median
and cubital nervures pursuing a transverse or recurrent course across
the wing, divide its area into a number of areolets or "cells," that
are of importance in classification. Among many of the smaller
Hymenoptera we find that the wings are almost destitute of nervures.
In the hind-wings--on account of their reduced size--the nervures are
even more reduced than in the fore-wings.
The legs of Hymenoptera are of the typical insectan form, and the foot
is usually composed of five segments. In many families the trochanter
appears to be represented by two small segments, there being thus an
extra joint in the leg. It is almost certain that the distal of these
two segments really belongs to the thigh, but the ordinary
nomenclature will be used in the present article, as this character is
of great importance in discriminating families, and the two segments
in question are referred to the trochanter by most systematic writers.
[Illustration: After C. Janet, _Aiguillon de la Myrmica rubra_ (Paris,
1898).
FIG. 5.--Ovipositor or Sting of Red Ant (_Myrmica rubra_) Queen.
Magnified. The right sheath C (outer process of the ninth abdominal
segment--9) is shown in connexion with the guide B formed by the inner
processes of the 9th segment. The stylet A (process of the 8th
abdominal segment--8) is turned over to show its groove a, which works
along the tongue or rail b.]
The typical insectan ovipositor, so well developed among the
Hymenoptera, consists of three pairs of processes (gonapophyses) two
of which belong to the ninth abdominal segment and one to the eighth.
The latter are the cutting or piercing stylets (fig. 5, A) of the
ovipositor, while the two outer processes of the ninth segment are
modified into sheaths or feelers (fig. 5, C) and the two inner
processes form a guide (fig. 5, B) on which the stylets work, tongues
or rails on the "guide" fitting accurately into longitudinal grooves
on the stylet. In the different families of the Hymenoptera, there are
various modifications of the ovipositor, in accord with the habits of
the insects and the purposes to which the organ is put. The sting of
wasps, ants and bees is a modified ovipositor and is used for
egg-laying by the fertile females, as well as for defence. Most male
Hymenoptera have processes which form claspers or genital armature.
These processes are not altogether homologous with those of the
ovipositor, being formed by inner and outer lobes of a pair of
structures on the ninth abdominal segment.
Many points of interest are to be noted in the internal structure of
the Hymenoptera. The gullet leads into a moderate-sized crop, and
several pairs of salivary glands open into the mouth. The crop is
followed by a proventriculus which, in the higher Hymenoptera, forms
the so-called "honey stomach," by the contraction of whose wails the
solid and liquid food can be separated, passed on into the digestive
stomach, or held in the crop ready for regurgitation into the mouth.
Behind the digestive stomach are situated, as usual, intestine and
rectum, and the number of kidney (Malpighian) tubes varies from only
six to over a hundred, being usually great.
In the female, each ovary consists of a large number of ovarian tubes,
in which swollen chambers containing the egg-cells alternate with
smaller chambers enclosing nutrient material. In connexion with the
ovipositor are two poison-glands, one acid and the other alkaline in
its secretion. The acid gland consists of one, two or more tubes, with
a cellular coat of several layers, opening into a reservoir whence
the duct leads to the exterior. The alkaline gland is an irregular
tube with a single cellular layer, its duct opening alongside that of
the acid reservoir. These glands are most strongly developed when the
ovipositor is modified into a sting.
_Development._--Parthenogenesis is of normal occurrence in the
life-cycle of many Hymenoptera. There are species of gall-fly in which
males are unknown, the unfertilized eggs always developing into
females. On the other hand, in certain saw-flies and among the higher
families, the unfertilized eggs, capable of development, usually give
rise to male insects (see BEE). The larvae of most saw-flies feeding
on the leaves of plants are caterpillars (fig. 6, b) with numerous
abdominal pro-legs, but in most families of Hymenoptera the egg is
laid in such a situation that an abundant food-supply is assured
without exertion on the part of the larva, which is consequently a
legless grub, usually white in colour, and with soft flexible cuticle
(fig. 7, a). The organs and instincts for egg-laying and
food-providing are perhaps the most remarkable features in the economy
of the Hymenoptera. Gall-fly grubs are provided with vegetable food
through the eggs being laid by the mother insect within plant tissues.
The ichneumon pierces the body of a caterpillar and lays her eggs
where the grubs will find abundant animal food. A digging-wasp hunts
for insect prey and buries it with the egg, while a true wasp feeds
her brood with captured insects, as a bird her fledglings. Bees store
honey and pollen to serve as food for their young. Thus we find
throughout the order a degree of care for offspring unreached by other
insects, and this family-life has, in the best known of the
Hymenoptera--ants, wasps and bees--developed into an elaborate social
organization.
_Social Life._--The development of a true insect society among the
Hymenoptera is dependent on a differentiation among the females between
individuals with well-developed ovaries ("queens") whose special
function is reproduction; and individuals with reduced or aborted
ovaries ("workers") whose duty is to build the nest, to gather food and
to tend and feed the larvae. Among the wasps the workers may only differ
from the queens in size, and individuals intermediate between the two
forms of female may be met with. Further, the queen wasp, and also the
queen humble-bee, commences unaided the work of building and founding a
new nest, being afterwards helped by her daughters (the workers) when
these have been developed. In the hive-bee and among ants, on the other
hand, there are constant structural distinctions between queen and
worker, and the function of the queen bee in a hive is confined to
egg-laying, the labour of the community being entirely done by the
workers. Many ants possess several different forms of worker, adapted
for special duties. Details of this fascinating subject are given in the
special articles ANT, BEE and WASP (q.v.).
_Habits and Distribution._--Reference has been already made to the
various methods of feeding practised by Hymenoptera in the larval stage,
and the care taken of or for the young throughout the order leads in
many cases to the gathering of such food by the mother or nurse. Thus,
wasps catch flies; worker ants make raids and carry off weak insects of
many kinds; bees gather nectar from flowers and transform it into honey
within their stomachs--largely for the sake of feeding the larvae in the
nest. The feeding habits of the adult may agree with that of the larva,
or differ, as in the ease of wasps which feed their grubs on flies, but
eat principally vegetable food themselves. The nest-building habit is
similarly variable. Digging wasps make simple holes in the ground; many
burrowing bees form branching tunnels; other bees excavate timber or
make their brood-chambers in hollow plant-stems; wasps work up with
their saliva vegetable fibres bitten off tree-bark to make paper; social
bees produce from glands in their own bodies the wax whence their
nest-chambers are built. The inquiline habit ("cuckoo-parasitism"), when
one species makes use of the labour of another by invading the nest and
laying her eggs there, is of frequent occurrence among Hymenoptera; and
in some cases the larva of the intruder is not content with taking the
store of food provided, but attacks and devours the larva of the host.
Most Hymenoptera are of moderate or small size, the giants of the
order--certain saw-flies and tropical digging-wasps--never reach the bulk
attained by the largest beetles, while the wing-spread is narrow compared
with that of many dragon-flies and moths. On the other hand, there are
thousands of very small species, and the tiny "fairy-flies"
(_Mymaridae_), whose larvae live as parasites in the eggs of various
insects, are excessively minute for creatures of such complex
organization. Hymenoptera are probably less widely distributed than
Aptera, Coleoptera or Diptera, but they are to be found in all except the
most inhospitable regions of the globe. The order is, with few
exceptions, terrestrial or aerial in habit. Comparatively only a few
species are, for part of their lives, denizens of fresh water; these, as
larvae, are parasitic on the eggs or larvae of other aquatic insects, the
little hymenopteron, _Polynema natans_, one of the "fairy-flies"--swims
through the water by strokes of her delicate wings in search of a
dragon-fly's egg in which to lay her own egg, while the rare _Agriotypus_
dives after the case of a caddis-worm. It is of interest that the waters
have been invaded by the parasitic group of the Hymenoptera, since in
number of species this is by far the largest of the order. No group of
terrestrial insects escapes their attacks--even larvae boring in wood are
detected by ichneumon flies with excessively long ovipositors. Not a few
cases are known in which a parasitic larva is itself pierced by the
ovipositor of a "hyperparasite," and even the offspring of the latter may
itself fall a victim to the attack of a "tertiary parasite."
_Fossil History._--Very little is known of the history of the
Hymenoptera previous to the Tertiary epoch, early in which, as we know
from the evidence of many Oligocene and Miocene fossils, all the more
important families had been differentiated. Fragments of wings from
the Lias and Oolitic beds have been referred to ants and bees, but the
true nature of these remains is doubtful.
_Classification._--Linnaeus divided the Hymenoptera into two
sections--the Terebrantia, whose females possess a cutting or piercing
ovipositor, and the Aculeata, in which the female organ is modified into
a sting. This nomenclature was adopted by P. A. Latreille and has been
in general use until the present day. A closely similar division of the
order results from T. Hartig's character drawn from the
trochanter--whether of two segments or undivided--the groups being
termed respectively Ditrocha and Monotrocha. But the most natural
division is obtained by the separation of the saw-flies as a primitive
sub-order, characterized by the imperfect union of the first abdominal
segment with the thorax, and by the broad base of the abdomen, so that
there is no median constriction or "waist," and by the presence of
thoracic legs--usually also of abdominal pro-legs--in the larva. All the
other families of Hymenoptera, including the gall-flies, ichneumons and
aculeates, have the first abdominal segment closely united with the
thorax, the second abdominal segment constricted so as to form a narrow
stalk or "waist," and legless larvae without a hinder outlet to the
food-canal. These two sub-orders are usually known as the
_Sessiliventra_ and _Petioliventra_ respectively, but the names
_Symphyta_ and _Apocrita_ proposed in 1867 by C. Gerstaecker have
priority, and should not be replaced.
_Symphyta._
This sub-order, characterized by the "sessile," broad-based abdomen,
whose first segment is imperfectly united with the thorax, and by the
usually caterpillar-like larvae with legs, includes the various groups
of saw-flies. Three leading families may be mentioned. The _Cephidae_,
or stem saw-flies, have an elongate pronotum, a compressed abdomen,
and a single spine on the shin of the fore-leg. The soft, white larvae
have the thoracic legs very small and feed in the stems of various
plants. _Cephus pygmaeus_ is a well-known enemy of corn crops. The
_Siricidae_ ("wood-wasps") are large elongate insects also with one
spine on each fore-shin, but with the pronotum closely joined to the
mesothorax. The ovipositor is long and prominent, enabling the female
insect to lay her eggs in the wood of trees, where the white larvae,
whose legs are excessively short, tunnel and feed. These insects are
adorned with bands of black and yellow, or with bright metallic
colours, and on account of their large size and formidable ovipositors
they often cause needless alarm to persons unfamiliar with their
habits. The _Tenthredinidae_, or true saw-flies, are distinguished by
two spines on each fore-shin, while the larvae are usually
caterpillars, with three pairs of thoracic legs, and from six to eight
pairs of abdominal pro-legs the latter not possessing the hooks found
on the pro-legs of lepidopterous caterpillars. Most saw-fly larvae
devour leaves, and the beautifully serrate processes of the ovipositor
are well adapted for egg-laying in plant tissues. Some saw-fly larvae
are protected by a slimy secretion (fig. 6, c) and a few live
concealed in galls. In the form of the feelers, the wing-neuration and
minor structural details there is much diversity among the saw-flies.
They have been usually regarded as a single family, but W. H. Ashmead
has lately differentiated eleven families of them.
_Apocrita._
This sub-order includes the vast majority of the Hymenoptera,
characterized by the narrowly constricted waist in the adult and by
the legless condition of the larva. The trochanter is simple in some
genera and divided in others. With regard to the minor divisions of
this group, great difference of opinion has prevailed among students.
In his recent classification Ashmead (1901) recognizes seventy-nine
families arranged under eight "super-families." The number of species
included in this division is enormous, and the multiplication of
families is, to some extent, a natural result of increasingly close
study. But the distinctions between many of these rest on
comparatively slight characters, and it is likely that the future
discovery of new genera may abolish many among such distinctions as
may now be drawn. It seems advisable, therefore, in the present
article to retain the wider conception of the family that has hitherto
contented most writers on the Hymenoptera. Ashmead's "super-families"
have, however, been adopted as--founded on definite structural
characters--they probably indicate relationship more nearly than the
older divisions founded mostly on habit. The Cynipoidea include the
gall-flies and their parasitic relations. In the Chalcidoidea,
Ichneumonoidea and Proctotrypoidea will be found nearly all the
"parasitic Hymenoptera" of older classifications. The Formicoidea are
the ants. The group of Fossores, or "digging-wasps," is divided by
Ashmead, one section forming the Sphecoidea, while the other, together
with the Chrysidae and the true wasps, make up the Vespoidea. The
Apoidea consists of the bees only.
[Illustration: After Marlatt, _Ent. Circ._ 26, U.S. Dept. Agric.
FIG. 6.--a, Pear Saw-fly (_Eriocampoides limacina_); b, larva without,
and c, with its slimy protective coat; e, cocoon; f, larva before
pupation; g, pupa, magnified; d, leaves with larvae.]
[Illustration: After Howard, _Ent. Tech. Bull._ 5 U.S. Dept. Agric.
FIG. 7.--Chalcid (_Dibrachys boucheanus_), a hyper-parasite.
a, Larva.
d, Its head more highly magnified.
b, Female fly.
c, Pupa of male.
e, Feeler.]
_Cynipoidea._--In this division the ovipositor issues from the ventral
surface of the abdomen; the pronotum reaches back to the tegulae; the
trochanter has two segments; the fore-wing (fig. 4, 2) has no stigma,
but one or two areolets. The feelers with twelve to fifteen segments
are thread-like and straight. All the insects included in this group
are small and form two families--the Cynipidae and the Figitidae. They
are the "gall-flies," many of the species laying eggs in various
plant-tissues where the presence of the larva causes the formation of
a pathological growth or gall, always of a definite form and
characteristic of the species; the "oak-apple" and the bedeguar of
the rose are familiar examples. Other flies of this group have the
inquiline habit, laying their eggs in the galls of other species,
while others again pierce the cuticle of maggots or aphids, in whose
bodies their larvae live as parasites.
_Chalcidoidea._--This division resembles the Cynipoidea in the
position of the ovipositor, and in the two segmented trochanters. The
fore-wing also has no stigma, and the whole wing is almost destitute
of nervures and areolets, while the pronotum does not reach back to
the tegulae, and the feelers are elbowed (fig. 7). The vast majority
of this group, including nearly 5000 known species, are usually
reckoned as a single family, the _Chalcididae_, comprising small
insects, often of bright metallic colours, whose larvae are parasitic
in insects of various orders. The "fig-insects," whose presence in
ripening figs is believed essential to the proper development of the
fruit, belong to _Blastophaga_ and other genera of this family. They
are remarkable in having wingless males and winged females. The
"polyembryonic" development of an _Encyrtus_, as studied by P.
Marchal, is highly remarkable. The female lays her egg in the egg of a
small ermine moth (_Hyponomeuta_) and the egg gives rise not to a
single embryo but to a hundred, which develop as the host-caterpillar
develops, being found at a later stage within the latter enveloped in
a flexible tube.
The _Mymaridae_ or "fairy-flies" are distinguished from the
_Chalcididae_ by their narrow fringed wings (figs. 4, 5) and by the
situation of the ovipositor just in front of the tip of the abdomen.
They are among the most minute of all insects and their larvae are
probably all parasitic in insects' eggs.
[Illustration: After Riley and Howard, _Insect Life_, vol. i.