Odonata

“ VI. Odonata—Dragon-flies.
(LIBELLULIDAE OF SOME AUTHORS)
Elongate Insects with very mobile head and large eyes, with small and inconspicuous antennae ending in a bristle; with four elongate wings sub-equal in size and similar in texture, of papyraceous consistency and having many veinlets, so that there exists a large number of small cells. All the legs placed more anteriorly than the wings. The earlier stages of the life are aquatic; there is great change in the appearance of the individual at the final ecdysis, but there is no pupal instar. ”

“ Nocturnal: species that fly or are active at night.
Nodal furrow: in Odonata; a transverse suture, beginning at a point in costal margin corresponding to the nodus, and extending toward inner margin.
Nodal sector: in Odonata; = media 2 (Comst.) : arises from upper sector of arculus near nodus and extends to outer margin.
Node: a knot or knob: in the plural refers to the small segment or segment between thorax and main portion of abdomen in ants.
Nodiform: in the form of a knot or knob.
Nodicorn: with antennae that have the apex of each joint swollen. ”

“ We have already, said that the Odonata consist of two very distinct divisions—Anisopterides and Zygopterides. The former group comprises the subfamilies Gomphinae, Cordulegasterinae, Aeschninae, Corduliinae, and Libellulinae,—Insects having the hinder wings slightly larger than the anterior pair; while the Zygopterides consist of only two subfamilies—Calepteryginae and Agrioninae; they have the wings of the two pairs equal in size, or the hinder a little the smaller. ”

“ The Odonata and Orthoptera have been transferred to modern cabinets in the general collection for safety. The collection contains some Types of Lepidoptera, described by J. Curtis, collected during Sir John Ross's second voyage in search of a north-west passage,1829-33, a few Selys Odonata Types, some syntypes of Walker Chalcidoidea, a number of Haliday specimens, insects collected in France by Curtis in 1830, and some taken by P. Walker in Sweden and Norway in 1836. ”

“ In the Odonata acinose glands are present in the imago, but not in the nymph until in its last stage, Poletaiew accounting for their absence in the earlier stages by the fact that the larva swallows more or less water while taking its food.
In the Coleoptera, as we have observed in Anopthalmus, there are three pairs of salivary glands (Fig. 74) . In the Blapsidæ these glands consist of many ramifying tubes united on each side of the œsophagus into a single duct; in others they are but slightly developed, while in still others they are wanting. ”

“ Ocular tubercles: in Aphids, are a group of prominent facets on the hinder part of each eye.
Oculi -us: the eyes: an eye: refers to the compound eyes.
Oculocephalic: applied to that pair of imaginal buds destined to produce the cephalic region in Hymenoptera.
Odona: toothed: applied to Odonata by Fabricius because of the long teeth on the maxilla and labium.
Odonata: net-veined insects with mandibulate mouth; head free; thorax agglutinate; wings similar, elongate, flat; metamorphosis incomplete; copulatory organs of male near base of abdomen, separate from the testes. ”

“ Quadrilateral: four-sided: formed or bounded by four lines: in Odonata, a space on the wings of Zygoptera bounded by the lower sector of arculus, the sub-median vein, a cross-vein between these two, and the lower part of arculus.
Queen: the actively reproducing female among worker insects.
Quiescent: not active: applied to the pupae in forms with complete metamorphosis.
Quiet: subdued: not conspicuous or contrasting in color or maculation. ”

“ Basilar cross-vein: Odonata; crosses the basilar space.
Basilar membrane: a thin membrane separating the cones and rods from the optic tract.
Basilar space: Odonata; that area at base of wings, between media and cubitus.
Basi-proboscis: basal third of the flexed proboscis of muscid flies.
Batesian mimicry: see mimicry.
Bathmis: see pterostigma.
Bave: the fluid silk as it is spun by caterpillars.
Beak: any notable prolongation of the front of the head: the snout in Rhynchophora: specifically, the jointed structure covering the lancets in the hemipterous mouth. ”

“ Squama: in Odonata, the sclerite that bears the palpus of both maxilla and labium: the scale-like first abdominal segment of some ants: a scale-like appendage covering the base of primaries in Lepidoptera, and so = patagium; q.v.: a small scale above the halteres in Diptera: in this order Packard uses squama for the lobed scale and restricts alula to the lobe-like appendage: Osten-Sacken uses squama for the posterior scale alone and antisquama for the anterior. ”

“ The number of species of Odonata or Libellulidae that have been described is somewhat less than two thousand, but constant additions are made to the number, and when the smaller and more fragile forms from the tropics are collected and worked out it will probably be found that the number of existing species is somewhere between five and ten thousand. They are distributed all over the world, but are most numerous in species in the warmer regions, and their predominance in any one locality is very much regulated by the existence of waters suitable for the early stages of their lives. ”

“ Post-media: Ephemerida; an apparently distinct vein between media and Cubitus (Comst.) .
Post-medial line: in Lepidoptera, = t.p. line: q.v.
Post-median: Diptera; those leg bristles situated above or behind the middle. Post-nodal cross-veins: in Odonata, the transverse veins between costa and radius 1, and radius 1 and media 1, from nodus to stigma, separating the post-nodal cells or spaces: = post-cubital cross-veins.
Post-nodal costal spaces: in Odonata, the cells below costal margin from nodus to stigma. ”

“ Short sector: in Odonata, = media 4 (Comst.) .
Shoulder: loosely applied to an obtuse angulation; more generally to the humeral angle of fore wings or elytra: the anterior angles of thorax in Lepidoptera; the angles of prothorax in Heteroptera: the lateral angles of metazona of pronotum in Orthoptera.
Sialisterium: a salivary gland.
Side: the lateral margin of the body.
Side piece: in genitalia of male Culicids the main lateral part of the clasping organ or basal segment of clasp.
Sides of thorax: in Odonata, includes the pleura of meso- and meta- thorax, less the meso-episterna. ”

“ Odonata; one or two pairs of hooked processes projecting from the ventral surface of the 2d abdominal segment of the male; usually termed genital hamules: in Hymenoptera; minute hooks on the anterior margin of secondaries used to unite them in flight with the inner margin of primaries: in tree crickets, hook-like processes of the male genitalia.
Hamus: Lepidoptera; a hook or loop attached to the under side of costal margin of primaries near base, to receive the frenulum of male moths.
Harpago -ones: the inner basal lobes of the clasping organs of d culicids also, more generally = harpes. ”

“ The typical number of abdominal segments (uromeres) , i.e. that occurring in each order of insects, is ten; and in certain families of Orthoptera, eleven. In the embryos, however, of the most generalized winged orders, Orthoptera (Fig. 199) , Dermaptera, and Odonata, eleven can be seen, while Heymons has recently detected twelve in blattid and Forficula embryos, and he claims that in the nymphs of certain Odonata there are twelve segments, the twelfth being 163represented by the anal or lateral plates. ”

“ Frontal vesicle: in Odonata; that elevated area on the vertex upon which the ocelli are situated.
Fronto-orbital bristles: in Diptera; are placed on each side of the front, just below the vertical bristles.
Fugitive: soon disappearing; not permanent.
Fulcrant: the trochanter when continued along the femur, as in Carabids.
Fulcrum: the chitinous envelope at the base of mouth in Diptera and Hymenoptera, covering the beginning of the oesophagus: any structure that serves as a support to another.. ”

“ Secretionary supplement: that part of a Diaspid scale extending beyond or around the pellicles.
Secretory: concerned in the process of secretion.
Sectores coronis: the tearing or cutting structures used by the Lepidoptera in working out of a cocoon.
Sectors: longitudinal veins in Odonata, which strike the principal veins at an angle, and usually reach the apex or hind margin: they are radial, subnodal, principal, nodal, median, short, and upper and lower of triangle: all of which see. ”

“ The larvæ and pupæ of these insects are aquatic, being often found under stones in water, whence the name. The adults are long, flattened insects, with long antennæ. The wings are ample and are somewhat folded or plaited, from which character the suborder takes its name.
Suborder Odonata (οθους, tooth) . This includes the Dragon-flies or Libellulidæ, the most common and the best known of the Neuroptera. The larva and the active pupa or nymph are aquatic and are predaceous, as is also the adult. A common species is represented at see Fig. ”

“ One result of his experiments is that insects only utilize their eyes to choose between a white luminous orifice in a dark chamber, or another orifice, or group of orifices, equally white. They are guided neither by odorous emanations nor by differences of color. He thinks that bees have as bad sight and act almost exactly as flies.
From numerous experiments on Odonata, Coleoptera, Lepidoptera, Diptera, and Hymenoptera Plateau arrives provisionally at the following conclusions:
1. Diurnal insects have need of a quick strong light, and cannot direct their movements in partial obscurity. ”

“ A good work on the British Odonata is still a desideratum. [344] In Britain about forty-six species are believed to be native. They are said to be of late years less numerous than they used to be. Notwithstanding their great powers of flight, dragon-flies are destroyed by birds of various kinds; several hawks are said to be very fond of them, and Merops persicus to line its nest with their wings. The number of Insects killed by dragon-flies in places where they are abundant must be enormous ”

“ Basal area: in wings: that space nearest the point where they are attached to the body: on the metanotum of Hymenoptera, the anterior of the three median cells or areas = 1st median area.
Basal cell: Diptera; st (Will.) , = radial 2 (Comst.) ; 2d (Will.) , = media (Comst.) ; Trichoptera; one, two or three cells enclosed by the branches that form-the post-costal or anal vein: Odonata; an elongate cell between radius and cubitus, just before the arculus.
Basalis: the principal mandibular sclerite, when sclerites are distinguishable, to which all other parts are jointed ”

“ Principal sector: in Odonata, extends from its point of separation From the median sector to the outer margin, at or just below the apex:= media 1 (Comst.) .
Principal sulcus: in Orthoptera, a transverse impression of the prothorax, at or behind the middle.
Priodont: applied to those forms of male Lucanids that have the smallest mandibles: see teleodont, mesodont, amphiodont.
Prismatic: formed like a prism: a play of colors similar to that produced through a prism.
Pro-: anterior: used as a prefix to designate the parts of the first thoracic segment. ”

“ When the larva sinks to the bottom, the velum soon disappears entirely, the foot becomes exceedingly long and narrow, while the shell is circular, strongly resembling a very young Cyclas.
Larvae of Unionidae.—The early stages of the development of Unio and Anodonta (so far as the species of North America, Europe, and Asia are concerned) is of extreme interest, from the remarkable fact that the young live for some time [147] parasitically attached to certain species of fresh-water fishes. ”

“ Its general appearance is rather that of the female of Odonestes potatoria than any other moth, somewhat agreeing with that species in the broad oval wings.
The head is rather small, but the eyes are large; the palpi are very long, forming a thick clavate brush of hairs; the maxillæ are almost rudimental, forming a very short flat tongue; the antennæ are short and slender; the wings are short and broadly ovate, the anterior rather acute at the apex, from which point to the base the hind margin of the wing forms a regular curve. ”

“ The little that is known of their natural history is almost limited to an account given by Giraud of the habits of Ceramius lusitanicus, of which species he found a colony near Briançon. The Insect makes nests in the earth; they are entered by means of a chimney-like passage analogous to what is formed by certain Odynerus; the gallery when completed is about six centimetres long, and at its extremity is an earthen cell in which the larva lives; this is fed by the mother, who brings to it from time to time a supply of a paste, described as being somewhat like dried honey. ”

“ We are quite astonished to see a nectar-drinker become a blood-drinker. But our astonishment ceases if we consider things more closely. The double method of feeding is more apparent than real: the crop which fills itself with sugary liquid does not gorge itself with game. The Odynerus, when digging into the body of her prey, does not touch the flesh, a fare absolutely scorned as contrary to her tastes; she satisfies herself with lapping up the defensive drop which the grub (The Larva of Chrysomela populi, the Poplar Leaf-beetle.—Translator's Note.) distils at the end of its intestine. ”

“ The centre of it was nearly filled by a luxurious couch of water-lily leaves and sedges, where, curled up snugly and fast asleep, four baby Ondatras lay with their faces hidden. They were like little Beavers, Phil thought, and just about the size of full-grown mice.
Their mother spoke in a hushed whisper lest she should disturb them.
"I'm glad that you think we are pleasant creatures," She said. "We do harm to no one, and live on roots and leaves, perfectly happy if we are but let alone. ”