Chapter IV: CYSTOPHORIDA (Cystonectae, Haeckel). With a very large (4)

_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.

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.

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.

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.]

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.

FIG. 8.--Ichneumon Fly (_Rhyssa per-suasoria_) ovipositing.]

_Ichneumonoidea._--The ten thousand known species included in this
group agree with the Cynipoidea and Chalcidoidea in the position of
the ovipositor and in the jointed trochanters, but are distinguished
by the fore-wing possessing a distinct stigma and usually a typical
series of nervures and areolets (figs. 4, 8). Many of the species are
of fair size. They lay their eggs (fig. 8) in the bodies of insects
and their larvae belonging to various orders. A few small families
such as the _Evaniidae_ and the _Stephanidae_ are included here, but
the vast majority of the group fall into two large families, the
_Ichneumonidae_ and the _Braconidae_, the former distinguished by the
presence of two median (or discoidal) cells in the fore-wing (figs. 4,
7), while the latter has only one (figs. 4, 6). Not a few of these
insects, however, are entirely wingless. On account of their work in
destroying plant-eating insects, the ichneumon-flies are of great
economic importance.

_Proctotrypoidea._--This group may be distinguished from the preceding
by the position of the ovipositor at the extreme apex of the abdomen,
and from the groups that follow (with very few exceptions) by the
jointed trochanters of the legs. The pronotum reaches back to the
tegulae. The _Pelecinidae_--included here by Ashmead--are large
insects with remarkably elongate abdomens and undivided trochanters.
All the other members of the group may be regarded as forming a single
family--the _Proctotrypidae_, including an immense number of small
parasitic Hymenoptera, not a few of which are wingless. Of special
interest are the transformations of _Platygaster_, belonging to this
family, discovered by M. Ganin, and familiarized to English readers
through the writings of Sir J. Lubbock (Lord Avebury). The first larva
is broad in front and tapers behind to a "tail" provided with two
divergent processes, so that it resembles a small crustacean. It lives
in the grub of a gall-midge and it ultimately becomes changed into the
usual white and fleshy hymenopterous larva. The four succeeding
sections, in which the ovipositor is modified into a sting (always
exserted from the tip of the abdomen) and the trochanters are with few
exceptions simple, form the _Aculeata_ of Linnaeus.

_Formicoidea._--The ants which form this group are readily
distinguished by the differentiation of the females into winged
"queens" and wingless "workers." The pronotum extends back to the
wing-bases, and the "waist" is greatly constricted and marked by one
or two "nodes." The differentiation of the females leads to a complex
social life, the nesting habits of ants and the various industries
that they pursue being of surpassing interest (see ANT).

_Vespoidea._--This section includes a number of families characterized
by the backward extension of the prothorax to the tegulae and
distinguished from the ants by the absence of "nodes" at the base of
the abdomen. The true wasps have the fore-wings folded lengthwise when
at rest and the fore-legs of normal build--not specialized for
digging. The _Vespidae_ or social wasps have "queens" and "workers"
like the ants, but both these forms of female are winged; the claws on
their fret are simple. In the _Eumenidae_ or solitary wasps the female
sex is undifferentiated, and the foot claws are toothed. (For the
habits of these insects see WASP.) The _Chrysididae_ or ruby wasps are
small insects with a very hard cuticle exhibiting brilliant metallic
colours--blue, green and crimson. Only three or four abdominal
segments are visible, the hinder segments being slender and retracted
to form a telescope-like tube in which the ovipositor lies. When the
ovipositor is brought into use this tube is thrust out. The eggs are
laid in the nests of various bees and wasps, the chrysid larva living
as a "cuckoo" parasite. The _Trigonalidae_, a small family whose
larvae are parasitic in wasps' nests, also probably belong here.

The other families of the _Vespoidea_ belong to the series of
"Fossores" or digging-wasps. In two of the families--the _Mutillidae_
and _Thynnidae_--the females are wingless and the larvae live as
parasites in the larvae of other insects; the female _Mutilla_ enters
bumble-bees' nests and lays her eggs in the bee-grubs. In the other
families both sexes are winged, and the instinct and industry of the
females are among the most wonderful in the Hymenoptera. They make
burrows wherein they place insects or spiders which they have caught
and stung, laying their eggs beside the victim so that the young
larvae find themselves in presence of an abundant and appropriate
food-supply. Valuable observations on the habits of these insects are
due to J. H. Fabre and G. W. and E. Peckham. The prey is sometimes
stung in the neighbourhood of the nerve ganglia, so that it is
paralysed but not killed, the grub of the fossorial wasp devouring its
victim alive; but this instinct varies in perfection, and in many
cases the larva flourishes equally whether its prey be killed or not.
The females have a wonderful power of finding their burrows on
returning from their hunting expeditions. Among the Vespoid families
of fossorial wasps, the _Pompilidae_ are the most important. They are
recognizable by their slender and elongate hind-legs; many of them
provision their burrows with spiders. The _Sapygidae_ are parasitic on
bees, while the _Scoliidae_ are large, robust and hairy insects, many
of which prey upon the grubs of chafers.

_Sphecoidea._--In this division are included the rest of the
"digging-wasps," distinguished from the _Vespoidea_ by the short
pronotum not reaching backward to the tegulae. They have usually been
reckoned as forming a single, very large family--the _Sphegidae_--but
ten or twelve subdivisions of the group are regarded as distinct
families by Ashmead and others. Great diversity is shown in the
details of structure, habits and nature of the prey. Species of
_Sphex_, studied by Fabre, provisioned their brood-chambers with
crickets. _Pelopoeus_ hunts spiders, while _Ammophila_ catches
caterpillars for the benefit of her young. Fabre states that the
last-named insect uses a stone for the temporary closing of her
burrow, and the Peckhams have seen a female _Ammophila_ take a stone
between her mandibles and use it as a hammer for pounding down the
earth over her finished nest. The habits of _Bembex_ are of especial
interest. The female, instead of provisioning her burrow with a supply
of food that will suffice the larva for its whole life, brings fresh
flies with which she regularly feeds her young. In this instinct we
have a correspondence with the habits of social wasps and bees. Yet it
may be thought that the usual instinct of the "digging-wasps" to
capture and store up food in an underground burrow for the benefit of
offspring which they will never see is even more surprising. The habit
of some genera is to catch the prey before making their tunnel, but
more frequently the insect digs her nest, and then hunts for prey to
put into it.

_Apoidea._--The bees which make up this group agree with the
Sphecoidea in the short pronotum, but may be distinguished from all
other Hymenoptera by the widened first tarsal segment and the plumose
hairs on head and body. They are usually regarded as forming a single
family--the _Apidae_--but there is very great diversity in structural
details, and Ashmead divides them into fourteen families. The
"tongue," for example, is short and obtuse or emarginate in _Colletes_
and _Prosopis_, while in all other bees it is pointed at the tip. But
in _Andrena_ and its allies it is comparatively short, while in the
higher genera, such as _Apis_ and _Bombus_, it is elongate and
flexible, forming a most elaborate and perfect organ for taking liquid
food. Bees feed on honey and pollen. Most of the genera are "solitary"
in habit, the female sex being undifferentiated; but among the
humble-bees and hive-bees we find, as in social wasps and ants, the
occurrence of workers, and the consequent elaboration of a wonderful
insect-society. (See BEE.)

BIBLIOGRAPHY.--The literature of several special families of the
Hymenoptera will be found under the articles ANT, BEE, ICHNEUMON-FLY,
WASP, &c., referred to above. Among earlier students on structure may
be mentioned P. A. Latreille, _Familles naturelles du règne animal_
(Paris, 1825), who recognized the nature of the "median segment." C.
Gerstaecker (_Arch. f. Naturg._ xx., 1867) and F. Brauer (_Sitzb. K.
Akad. Wiss. Wien._ lxxxv., 1883) should also be consulted on this
subject. For internal anatomy, specially the digestive organs, see L.
Dufour, _Mém. savants étrangers_, vii. (1841), and _Ann. Sci. Nat.
Zool._ (4), i. 1854. For nervous system H. Viallanes, _Ann. Sci. Nat.
Zool._ (7), ii. iv. 1886-1887, and F. C. Kenyon, _Journ. Comp.
Neurol._ vi., 1896. For poison and other glands, see L. Bordas, _Ann.
Sci. Nat. Zool._ (7) xix., 1895. For the sting and ovipositor H.
Dewitz, _Zeits. wiss. Zool._ xxv., 1874, xxviii., 1877, and F. Zander,
_ib._ lxvi., 1899. For male genital armature S. A. Peytoureau,
_Morphologie de l'armure génitale des insectes_ (Bordeaux, 1895),
and E. Zander, Zeits. wiss. Zool. lxvii., 1900. The systematic student
of Hymenoptera is greatly helped by C. G. de Dalla Torre's _Catalogus
Hymenopterorum_ (10 vols., Leipzig, 1893-1902). For general
classifications see F. W. Konow, _Entom. Nachtr._ (1897), and W. H.
Ashmead, _Proc. U.S. Nat. Mus._ xxiii., 1901; the latter paper deals
also especially with the Ichneumonoidea of the globe. For habits and
life histories of Hymenoptera see J. Lubbock (Lord Avebury), _Ants,
Bees and Wasps_ (9th ed., London, 1889); C. Janet, _Études sur les
fourmis, les guêpes et les abeilles_ (Paris, &c., 1893 and onwards);
and G. W. and E. G. Peckham, _Instincts and Habits of Solitary Wasps_
(Madison, Wis. U.S.A., 1898). Monographs of most of the families of
British Hymenoptera have now been published. For saw-flies and
gall-flies, see P. Cameron's _British Phytophagous Hymenoptera_ (4
vols., London, _Roy. Soc._, 1882-1893). For Ichneumonoidea, C.
Morley's _Ichneumons of Great Britain_ (Plymouth, 1903, &c.), and T.
A. Marshall's "British Braconidae," _Trans. Entom. Soc._, 1885-1899.
The smaller parasitic Hymenoptera have been neglected in this country
since A. H. Haliday's classical papers _Entom. Mag._ i.-v.,
(1833-1838) but Ashmead's "North American Proctotrypidae" (_Bull. U.S.
Nat. Mus._ xlv., 1893) is valuable for the European student. For the
Fossores, wasps, ants and bees see E. Saunders, _Hymenoptera Aculeata
of the British Islands_ (London, 1896). Exhaustive references to
general systematic works will be found in de Dalla Torre's _Catalogue_
mentioned above. Of special value to English students are C. T.
Bingham's _Fauna of British India_, "Hymenoptera" (London, 1897 and
onwards), and P. Cameron's volumes on Hymenoptera in the _Biologia
Centrali-Americana_. F. Smith's _Catalogues of Hymenoptera in the
British Museum_ (London, 1853-1859) are well worthy of study.
(G. H. C.)

HYMETTUS (Ital. Monte Matto, hence the modern name Trello Vouni), a mountain in Attica, bounding the Athenian plain on the S.E. Height, 3370 ft. It was famous in ancient times for its bees, which gathered honey of peculiar flavour from its aromatic herbs; their fame still persists. The spring mentioned by Ovid (_Ars Amat._ iii. 687) is probably to be recognized near the monastery of Syriani or Kaesariani on the western slope. This may be identical with that known as [Greek: Kyllon Pêra], said to be a remedy for barrenness in women. The marble of Hymettus, which often has a bluish tinge, was used extensively for building in ancient Athens, and also, in early times, for sculpture; but the white marble of Pentelicus was preferred for both purposes.

See E. Dodwell, _Classical and Topographical Tour_ (1819), i. 483.

HYMNS.--1. _Classical Hymnody._--The word "hymn" ([Greek: hymnos]) was employed by the ancient Greeks[1] to signify a song or poem composed in honour of gods, heroes or famous men, or to be recited on some joyful, mournful or solemn occasion. Polymnia was the name of their lyric muse. Homer makes Alcinous entertain Odysseus with a "hymn" of the minstrel Demodocus, on the capture of Troy by the wooden horse. The _Works and Days_ of Hesiod begins with an invocation to the Muses to address hymns to Zeus, and in his _Theogonia_ he speaks of them as singing or inspiring "hymns" to all the divinities, and of the bard as "their servant, hymning the glories of men of old, and of the gods of Olympus." Pindar calls by this name odes, like his own, in praise of conquerors at the public games of Greece. The Athenian dramatists (Euripides most frequently) use the word and its cognate verbs in a similar manner; they also describe by them metrical oracles and apophthegms, martial, festal and hymeneal songs, dirges and lamentations or incantations of woe.

Hellenic hymns, according to this conception of them, have come down to us, some from a very early and others from a late period of Greek classical literature. Those which passed by the name of Homer[2] were already old in the time of Thucydides. They are mythological poems (several of them long), in hexameter verse--some very interesting. That to Apollo contains a traditionary history of the origin and progress of the Delphic worship; those on Hermes and on Dionysus are marked by much liveliness and poetical fancy. Hymns of a like general character, but of less interest (though these also embody some fine poetical traditions of the Greek mythology, such as the story of Teiresias, and that of the wanderings of Leto), were written in the 3rd century before Christ, by Callimachus of Cyrene. Cleanthes, the successor of Zeno, composed (also in hexameters) an "excellent and devout hymn" (as it is justly called by Cudworth, in his _Intellectual System_) to Zeus, which is preserved in the _Eclogae_ of Stobaeus, and from which Aratus borrowed the words, "For we are also His offspring," quoted by St Paul at Athens. The so-called Orphic hymns, in hexameter verse, styled [Greek: teletai], or hymns of initiation into the "mysteries" of the Hellenic religion, are productions of the Alexandrian school,--as to which learned men are not agreed whether they are earlier or later than the Christian era.

The Romans did not adopt the word "hymn"; nor have we many Latin poems of the classical age to which it can properly be applied. There are, however, a few--such as the simple and graceful "Dianae sumus in fide" ("Dian's votaries are we") of Catullus, and "Dianam tenerae dicite virgines" ("Sing to Dian, gentle maidens") of Horace--which approach much more nearly than anything Hellenic to the form and character of modern hymnody.

2. _Hebrew Hymnody._--For the origin and idea of Christian hymnody we must look, not to Gentile, but to Hebrew sources. St Augustine's definition of a hymn, generally accepted by Christian antiquity, may be summed up in the words, "praise to God with song" ("cum cantico"); Bede understood the "canticum" as properly requiring metre; though he thought that what in its original language was a true hymn might retain that character in an unmetrical translation. Modern use has enlarged the definition; Roman Catholic writers extend it to the praises of saints; and the word now comprehends rhythmical prose as well as verse, and prayer and spiritual meditation as well as praise.

The modern distinction between psalms and hymns is arbitrary (see PSALMS). The former word was used by the LXX. as a generic designation, probably because it implied an accompaniment by the psaltery (said by Eusebius to have been of very ancient use in the East) or other instruments. The cognate verb "psallere" has been constantly applied to hymns, both in the Eastern and in the Western Church; and the same compositions which they described generically as "psalms" were also called by the LXX. "odes" (i.e. songs) and "hymns." The latter word occurs, e.g. in Ps. lxxii. 20 ("the hymns of David the son of Jesse"), in Ps. lxv. 1, and also in the Greek titles of the 6th, 54th, 55th, 67th and 76th (this numbering of the psalms being that of the English version, not of the LXX.). The 44th chapter of Ecclesiasticus, "Let us now praise famous men," &c., is entitled in the Greek [Greek: paterôn hymnos], "The Fathers' Hymn." Bede speaks of the whole book of Psalms as called "liber hymnorum," by the universal consent of Hebrews, Greeks and Latins.

In the New Testament we find our Lord and His apostles singing a hymn ([Greek: hymnêsantes exêlthon]), after the institution of the Lord's Supper; St Paul and Silas doing the same ([Greek: hymnoun ton theon]) in their prison at Philippi; St James recommending psalm-singing ([Greek: psalletô]), and St Paul "psalms and hymns and spiritual songs" ([Greek: psalmois kai hymnois kai ôdais pneumatikais]) St Paul also, in the 14th chapter of the first epistle to the Corinthians, speaks of singing ([Greek: psalô]) and of every man's psalm ([Greek: hekastos hymôn psalmon echei]). In a context which plainly has reference to the assemblies of the Corinthian Christians for common worship. All the words thus used were applied by the LXX. to the Davidical psalms; it is therefore possible that these only may be intended, in the different places to which we have referred. But there are in St Paul's epistles several passages (Eph. v. 14; 1 Tim. iii. 16; 1 Tim. vi. 15, 16; 2 Tim. ii. 11, 12) which have so much of the form and character of later Oriental hymnody as to have been supposed by Michaelis and others to be extracts from original hymns of the Apostolic age. Two of them are apparently introduced as quotations, though not found elsewhere in the Scriptures. A third has not only rhythm, but rhyme. The thanksgiving prayer of the assembled disciples, recorded in Acts iv., is both in substance and in manner poetical; and in the canticles, "Magnificat," "Benedictus," &c., which manifestly followed the form and style of Hebrew poetry, hymns or songs, proper for liturgical use, have always been recognized by the church.

3. _Eastern Church Hymnody._--The hymn of our Lord, the precepts of the apostles, the angelic song at the nativity, and "Benedicite omnia opera" are referred to in a curious metrical prologue to the hymnary of the Mozarabic Breviary as precedents for the practice of the Western Church. In this respect, however, the Western Church followed the Eastern, in which hymnody prevailed from the earliest times.

Therapeutae.

Philo describes the Theraputae (q.v.) of the neighbourhood of Alexandria as composers of original hymns, which (as well as old) were sung at their great religious festivals--the people listening in silence till they came to the closing strains, or refrains, at the end of a hymn or stanza (the "acroteleutia" and "ephymnia"), in which all, women as well as men, heartily joined. These songs, he says, were in various metres (for which he uses a number of technical terms); some were choral, some not; and they were divided into variously constructed strophes or stanzas. Eusebius, who thought that the Theraputae were communities of Christians, says that the Christian practice of his own day was in exact accordance with this description.

Antiphonal singing.

The practice, not only of singing hymns, but of singing them antiphonally, appears, from the well-known letter of Pliny to Trajan, to have been established in the Bithynian churches at the beginning of the 2nd century. They were accustomed "stato die ante lucem convenire, carmenque Christo, quasi Deo, dicere _secum invicem_." This agrees well, in point of time, with the tradition recorded by the historian Socrates, that Ignatius (who suffered martyrdom about A.D. 107) was led by a vision or dream of angels singing hymns in that manner to the Holy Trinity to introduce antiphonal singing into the church of Antioch, from which it quickly spread to other churches. There seems to be an allusion to choral singing in the epistle of Ignatius himself to the Romans, where he exhorts them, "[Greek: choros genomenoi]" ("having formed themselves into a choir"), to "sing praise to the Father in Christ Jesus." A statement of Theodoret has sometimes been supposed to refer the origin of antiphonal singing to a much later date; but this seems to relate only to the singing of Old Testament Psalms ([Greek: tên Dauidikên melôdian]), the alternate chanting of which, by a choir divided into two parts, was (according to that statement) first introduced into the church of Antioch by two monks famous in the history of their time, Flavianus and Diodorus, under the emperor Constantius II.

2nd century.

3rd century.

Other evidence of the use of hymns in the 2nd century is contained in a fragment of Caius, preserved by Eusebius, which refers to "all the psalms and odes written by faithful brethren from the beginning," as "hymning Christ, the Word of God, as God." Tertullian also, in his description of the "Agapae," or love-feasts, of his day, says that, after washing hands and bringing in lights, each man was invited to come forward and sing to God's praise something either taken from the Scriptures or of his own composition ("ut quisque de Sacris Scripturis vel proprio ingenio potest"). George Bull, bishop of St David's, believed one of those primitive compositions to be the hymn appended by Clement of Alexandria to his _Paedagogus_; and Archbishop Ussher considered the ancient morning and evening hymns, of which the use was enjoined by the _Apostolical Constitutions_, and which are also mentioned in the "Tract on Virginity" printed with the works of St Athanasius, and in St Basil's treatise upon the Holy Spirit, to belong to the same family. Clement's hymn, in a short anapaestic metre, beginning [Greek: stomion pôlôn adaôn] (or, according to some editions, [Greek: basileu hagiôn, loge pandamatôr]--translated by the Rev. A. Chatfield, "O Thou, the King of Saints, all-conquering Word"), is rapid, spirited and well-adapted for singing. The Greek "Morning Hymn" (which, as divided into verses by Archbishop Ussher in his treatise _De Symbolis_, has a majestic rhythm, resembling a choric or dithyrambic strophe) is the original form of "Gloria in Excelsis," still said or sung, with some variations, in all branches of the church which have not relinquished the use of liturgies. The Latin form of this hymn (of which that in the English communion office is an exact translation) is said, by Bede and other ancient writers, to have been brought into use at Rome by Pope Telesphorus, as early as the time of the emperor Hadrian. A third, the Vesper or "Lamp-lighting" hymn ("[Greek: phôs hilaron hagias doxês]"--translated by Canon Bright "Light of Gladness, Beam Divine"), holds its place to this day in the services of the Greek rite. In the 3rd century Origen seems to have had in his mind the words of some other hymns or hymn of like character, when he says (in his treatise _Against Celsus_): "We glorify in hymns God and His only begotten Son; as do also the Sun, the Moon, the Stars and all the host of heaven. All these, in one Divine chorus, with the just among men, glorify in hymns God who is over all, and His only begotten Son." So highly were these compositions esteemed in the Syrian churches that the council which deposed Paul of Samosata from the see of Antioch in the time of Aurelian justified that act, in its synodical letter to the bishops of Rome and Alexandria, on this ground (among others) that he had prohibited the use of hymns of that kind, by uninspired writers, addressed to Christ.

After the conversion of Constantine, the progress of hymnody became closely connected with church controversies. There had been in Edessa, at the end of the 2nd or early in the 3rd century, a Gnostic writer of conspicuous ability, named Bardesanes, who was succeeded, as the head of his sect or school, by his son Harmonius. Both father and son wrote hymns, and set them to agreeable melodies, which acquired, and in the 4th century still retained, much local popularity. Ephraem Syrus, the first voluminous hymn-writer whose works remain to us, thinking that the same melodies might be made useful to the faith, if adapted to more orthodox words, composed to them a large number of hymns in the Syriac language, principally in tetrasyllabic, pentasyllable and heptasyllabic metres, divided into strophes of from 4 to 12, 16 and even 20 lines each. When a strophe contained five lines, the fifth was generally an "ephymnium," detached in sense, and consisting of a prayer, invocation, doxology or the like, to be sung antiphonally, either in full chorus or by a separate part of the choir. The _Syriac Chrestomathy_ of August Hahn (Leipzig, 1825), and the third volume of H. A. Daniel's _Thesaurus Hymnologicus_ (Leipzig, 1841-1856), contain specimens of these hymns. Some of them have been translated into (unmetrical) English by the Rev. Henry Burgess (_Select Metrical Hymns of Ephrem Syrus_, &c., 1853). A considerable number of those so translated are on subjects connected with death, resurrection, judgment, &c., and display not only Christian faith and hope, but much simplicity and tenderness of natural feeling. Theodoret speaks of the spiritual songs of Ephraem as very sweet and profitable, and as adding much, in his (Theodoret's) time, to the brightness of the commemorations of martyrs in the Syrian Church.

The Greek hymnody contemporary with Ephraem followed, with some licence, classical models. One of its favourite metres was the Anacreontic; but it also made use of the short anapaestic, Ionic, iambic and other lyrical measures, as well as the hexameter and pentameter. Its principal authors were Methodius, bishop of Olympus, who died about A.D. 311, Synesius, who became bishop of Ptolemais in Cyrenaica in 410, and Gregory Nazianzen, for a short time (380-381) patriarch of Constantinople. The merits of these writers have been perhaps too much depreciated by the admirers of the later Greek "Melodists." They have found an able English translator in the Rev. Allen Chatfield (_Songs and Hymns of Earliest Greek Christian Poets_, London, 1876). Among the most striking of their works are [Greek: mnôeo Christe] ("Lord Jesus, think of me"), by Synesius; [Greek: se ton aphthiton monarchên] ("O Thou, the One Supreme") and [Greek: ti soi theleis genesthai] ("O soul of mine, repining"), by Gregory; also [Greek: anôthen parthenoi] ("The Bridegroom cometh"), by Methodius. There continued to be Greek metrical hymn-writers, in a similar style, till a much later date. Sophronius, patriarch of Jerusalem in the 7th century, wrote seven Anacreontic hymns; and St John Damascene, one of the most copious of the second school of "Melodists," was also the author of some long compositions in trimeter iambics.

Period of Arian controversy.

An important development of hymnody at Constantinople arose out of the Arian controversy. Early in the 4th century Athanasius had rebuked, not only the doctrine of Arius, but the light character of certain hymns by which he endeavoured to make that doctrine popular. When, towards the close of that century (398), St John Chrysostom was raised to the metropolitan see, the Arians, who were still numerous at Constantinople, had no places of worship within the walls; but they were in the habit of coming into the city at sunset on Saturdays, Sundays and the greater festivals, and congregating in the porticoes and other places of public resort, where they sung, all night through, antiphonal songs, with "acroteleutia" (closing strains, or refrains), expressive of Arian doctrine, often accompanied by taunts and insults to the orthodox. Chrysostom was apprehensive that this music might draw some of the simpler church people to the Arian side; he therefore organized, in opposition to it, under the patronage and at the cost of Eudoxia, the empress of Arcadius (then his friend), a system of nightly processional hymn-singing, with silver crosses, wax-lights and other circumstances of ceremonial pomp. Riots followed, with bloodshed on both sides, and with some personal injury to the empress's chief eunuch, who seems to have officiated as conductor or director of the church musicians. This led to the suppression, by an imperial edict, of all public Arian singing; while in the church the practice of nocturnal hymn-singing on certain solemn occasions, thus first introduced, remained an established institution.

Greek system of hymnody.

It is not improbable that some rudiments of the peculiar system of hymnody which now prevails throughout the Greek communion, and whose affinities are rather to the Hebrew and Syriac than to the classical forms, may have existed in the church of Constantinople, even at that time. Anatolius, patriarch of Constantinople in the middle of the 5th century, was the precursor of that system; but the reputation of being its proper founder belongs to Romanos, of whom little more is known than that he wrote hymns still extant, and lived towards the end of that century. The importance of that system in the services of the Greek church may be understood from the fact that Dr J. M. Neale computed four-fifths of the whole space (about 5000 pages) contained in the different service-books of that church to be occupied by hymnody, all in a language or dialect which has ceased to be anywhere spoken.

The system has a peculiar technical terminology, in which the words
"troparion," "ode," "canon" and "hirmus" ([Greek: eirmos]) chiefly
require explanation.

The _troparion_ is the unit of the system, being a strophe or stanza,
seen, when analysed, to be divisible into verses or clauses, with
regulated caesuras, but printed in the books as a single prose
sentence, without marking any divisions. The following (turned into
English, from a "canon" by John Mauropus) may be taken as an example:
"The never-sleeping Guardian, | the patron of my soul, | the guide of
my life, | allotted me by God, | I hymn thee, Divine Angel | of
Almighty God." Dr Neale and most other writers regard all these
"troparia" as rhythmical or modulated prose. Cardinal J. B. Pitra, on
the other hand, who in 1867 and 1876 published two learned works on
this subject, maintains that they are really metrical, and governed by
definite rules of prosody, of which he lays down sixteen. According to
him, each "troparion" contains from three to thirty-three verses; each
verse varies from two to thirteen syllables, often in a continuous
series, uniform, alternate or reciprocal, the metre being always
syllabic, and depending, not on the quantity of vowels or the position
of consonants, but on an harmonic series of accents.

In various parts of the services solitary troparia are sung, under
various names, "contacion," "oecos," "cathisma," &c., which mark
distinctions either in their character or in their use.

An _ode_ is a song or hymn compounded of several similar
"troparia,"--usually three, four or five. To these is always prefixed
a typical or standard "troparion," called the _hirmus_, by which the
syllabic measure, the periodic series of accents, and in fact the
whole structure and rhythm of the stanzas which follow it are
regulated. Each succeeding "troparion" in the same "ode" contains the
same number of verses, and of syllables in each verse, and similar
accents on the same or equivalent syllables. The "hirmus" may either
form the first stanza of the "ode" itself, or (as is more frequently
the case) may be taken from some other piece; and, when so taken, it
is often indicated by initial words only, without being printed at
length. It is generally printed within commas, after the proper rubric
of the "ode." A hymn in irregular "stichera" or stanzas, without a
"hirmus," is called "idiomelon." A system of three or four odes is
"triodion" or "tetraodion."

A _canon_ is a system of eight (theoretically nine) connected odes,
the second being always suppressed. Various pauses, relieved by the
interposition of other short chants or readings, occur during the
singing of a whole "canon." The final "troparion" in each ode of the
series is not unfrequently detached in sense (like the "ephymnia" of
Ephraem Syrus), particularly when it is in the (very common) form of a
"theotokion," or ascription of praise to the mother of our Lord, and
when it is a recurring refrain or burden.

There were two principal periods of Greek hymnography constructed on these principles--the first that of Romanos and his followers, extending over the 6th and 7th centuries, the second that of the schools which arose during the Iconoclastic controversy in the 8th century, and which continued for some centuries afterwards, until the art itself died out.

School of Romanos.