ORDER A P T E R A . WINGLESS. 



141 



The insects constituting this remarkable genus are well known under 

 the name of Plant-lice. They infest almost every species of vegetable in 

 innumerable quantities, occasioning the leaves to curl up, and often pre- 

 venting the growth of the young shoots, by the punctures they make for 

 the purpose of procuring the juices of the plant, on which they live. The 

 injuries which these little insignificant animals sometimes occasion, are 

 much more considerable than would at first be imagined, from their ex- 

 treme tenuity, weakness, and inactivity ; but then- increase is so rapid and 

 extensive, as to render them formidable enemies. The finest of our fruits 

 are thus often nipped in the bud, or arrested in a subsequent period of 

 their growth ; and indeed scarcely any of our esculent vegetables are free 

 from their attacks. The hop-grounds in Kent would, in some seasons, be 

 rendered almost barren by their swarms, had not nature provided an effi- 

 cient preventive. This consists in the circumstance of their forming the 

 favourite food of the larva of the ladybird (Coccinella), and of several spe- 

 cies of aphidivorous flies, particularly of the genus Syrphus of Fabricius. 

 These larva? fix themselves by the tail, in the midst of a host of aphides, 

 and extend or contract themselves so as to reach their prey ; and on seizing 

 one, it is held up in the air, whilst all the juices of the body are sucked 

 out, after which the skin is dropped. 



The species are very numerous, and but imperfectly understood, but 

 there is reason to believe, that very many plants nourish their own peculiar 

 aphides ; and it has been usual to name the species after the plants which 

 they principally inhabit, as Aphis Rosa?, A. Sambuci, A. Ulmi, c. 



Illustration : Aphis roses. 



ORDER VII. DIPTERA. TWO-WINGED. 



THE characteristics of the order Diptera may, in general terms, be thus 

 stated : Feet six ; wings two, ribbed and extended ; with two balancers 

 placed behind them, in the place of the second pair ; mouth consisting of 

 from two to six scaly bristle or lancet-like pieces shut in a sheath ; sheath, 

 in the form of a trunk or syphon, bent or jointed, often ending in two 

 lips, and generally furnished with a superior groove, and often provided 

 with two maxillary palpi, which are sometimes enclosed in the sheath. 



Several of the insects of this order, belonging to the genera Tipida, 

 Samvlia, Tabanies, and Sternoxus, incommode us and other animals with 

 their suckers, which often perforate the skin and leave irritable wounds. 

 Some, as the (Estri or Gadflies, deposit their eggs in the bodies of domestic 

 animals, and even sometimes in those of men themselves. Others, in the 

 same manner, infest our meats, cheese, and eatables, or in the form of 

 larva?, attack plants, and make extensive ravages in them. But as a sort of 

 compensation for these various injuries, these insects consume and destroy 

 great quantities of putrid animal and vegetable substances, or dissipate the 

 fetid and stagnant waters. 



ILLUSTRATIVE EXAMPLES. 



ECHINOMYIA. Antenna? with intermediate joint longer than the third ; 

 the lateral hair simple, and hid when the insect is at rest. 



The Echinomyia resembles in form the common house Flies ; but is 

 remarkable for the large size of its body, which is covered with scattered 

 long hairs, which are large, and, as it were, jointed at the base. The 

 wings are spread, and the abdomen is broader than long. The manners of 

 several of the species are comparatively well known : the perfect insects 

 live but a very short time, and are found principally on the flowers of um- 

 belliferous plants ; the females lay their eggs in the Caterpillars (larvae) and 

 grubs (pupcs) of various Lepidopteraus and some Coleopterous insects, 

 which they eventually destroy. 



Illustration : Echinomyia f era. 



CEROPLATUS. Antenna? longer than the head, subfusiform, compressed, 

 proboscis very short; palpi apparently without joints, very short. 



These insects are remarkable for the form of their antenna?, which re- 

 sembles a rasp or file. The abdomen is elongate and fusiform. The 

 larva? feed on mushrooms. 



Type of the genus, also our 



Illustration : Ceroplatus tipuloises. 



THEREVA (of Latr.) Antenna? fusiform, or elongated into a conical 

 form at the tips ; palpi withdrawn into the oval cavity. 



Type of the genus, T. plebeia. 

 Illustration : Thereva crassipennis. 



TABANUS. Antenna? as long or longer than the head, three-jointed, the 

 last joint awl-shaped and five-ringed ; proboscis shorter than the head, and 

 terminating in two large lips ; haustellum consisting of six sete ; palpi 

 nearly as long as the proboscis; head broad, transverse, sessile, in some 

 species furnished with stemmata, as well as large brilliant reticulated ejes, 

 but in others without stemmata ; abdomen sessile, of same breadth as the 

 thorax ; wings horizontal and widely separate at their tips. 



The Tabard very much resemble large flies, and are remarkable for their 

 beautifully-coloured large eyes, which in the male are divided by a very 

 narrow line in front, but in the female this line is much wider, and hence 

 forms a good sexual distinction ; their haustellum is furnished with six 

 setae, forming terrible instruments for puncturing the hides of cattle and 

 horses, which they attack fiercely in spring and autumn, making wounds 

 bigger than that of a large needle, from which the blood flows freely in 

 large drops like tears. From the spreading of the lips of the proboscis the 

 wound cannot be seen whilst the insect is at work, but the pain is very 

 severe ; and that produced by the Burning or Sand Fly of America and 

 the West Indies, supposed to belong to this genus, is so great, that it has 

 been compared to the pain which would be produced by a red-hot needle 

 or by a spark of fire. It seems, however, that this sanguinary disposition 

 belongs especially to the females, as the males are often noticed feeding on 

 flowers. They seem to be spread generally over the globe. 



Illustration : Tabanus niger. 



DIOPSIS. Antenna? palette-shaped, each inserted on a prolongation of the 

 side of the head into the form of a horn; the eyes situated at the end of 

 these horns ; trunk membranaceous, two-lipped, retractile. 



This curious genus was first noticed by Fabricius. 



Illustration : Diopsis Ichneumonea. 



ORDER VIII. APTERA. WINGLESS. 



THIS is the Order Suctoria of De Geer ; it includes one very well-known 

 genus the common Flea ; distinguished from all other insects by its oral 

 sucker, which consists of three pieces inclosed between the articulated 

 plates, and forming a cylindrical or conical beak. 



ILLUSTRATIVE EXAMPLES. 



PULEX. Antenna? short, three-jointed, the two basal joints obconic, the 

 terminal obtuse; palpi four-articulate, porrect; tongue slender, filiform, 

 transparent ; maxilla? lateral ; head small ; body compressed, apterous ; legs 

 long, formed for leaping ; coxa? very much elongate and large ; femora short ; 

 tibia? pilose ; tarsi five-jointed. 



Type of the genus, P. irritans (the Common Flea). 



There are nearly fifty species of this troublesome and active little insect. 



Illustrations : Pulex irritans, P. Chigoe. 



SECOND ARRANGEMENT OF INSECTS. 



THIS second arrangement is in accordance with the systems of recent 

 Naturalists. Only the principal genera illustrated in Plates III., IV., and 

 V. are noticed. 



ORDER I. COLEOPTEROUS INSECTS. 



ILLUSTRATIVE EXAMPLES. 



PLATE 3. 



ANTHIA. Corcelet, nearly heart-shaped ; the head not narrowed behind ; 

 no obvious neck, palpi filiform, labrum oval, and projecting to the base of 



