INSECTS WITHOUT WINGS. 



447 



assumes a new covering, which is called a 

 chrysalis, or the cone in the silkworm, in 

 which it continues hidden till it come forth a 

 perfect moth, or butterfly. 



The FOURTH ORDER is of those winged insects 

 which come from a worm instead of a cater- 

 pillar, and yet go through changes similar to 

 those which moths and butterflies are seen to 

 undergo. They are first excluded from the 

 egg as a worm, and then become a chrysalis; 

 in some, their wings and legs are seen ; in 

 others, the animal is quite detached from the 

 cone in which it is concealed ; but all at length 

 break their prison and come out perfect winged 

 animals ; some furnished with two wings, and 

 some with four. The wings of all these differ 

 from those of the butterfly and moth kind, by 

 not having the mealy scales which are ever 

 found on the wings of the former. In this 

 class we may place the numerous tribes of 

 gnats, beetles, bees, and flies. 



To these I will add, as a FIFTH ORDER, a nu- 

 merous tribe lately discovered, to which natu- 

 ralists have given the name of Zoophytes. 

 These do not go through the ordinary forms of 

 generation but may be propagated by dissection. 

 Some of these, though cut into a hundred parts, 



still retain life in each, and are endued with 

 such a vivacious principle, that every part 

 will in a short time become a perfect animal. 

 They seem a set of creatures placed between 

 animals and vegetables, and Inalce the shade 

 that connects animated and insensible nature. 

 To this class belong the polypus, the earth- 

 worm, and all the varieties of the sea-nettle. 



Having thus given a general distribution 

 of insects, I will proceed to describe eacli 

 class in the order I have mentioned them ; 

 beginning with insects without wings, as they 

 more nearly resemble the higher ranks of 

 nature, as well in their habits as their confor- 

 mation. 



CHAP. II. 



OF INSECTS WITHOUT WINGS. 



EVERT moment's observation furnishes us 

 with instances of insects without wings ; but 

 the difficulty is to distinguish those which are 

 condemned continually to lead reptile lives, 

 from such as only wait the happy moment of 



fasciatq, f. 141. Tribe v. Dolichopoda. Porphyrops 

 diaplianus. f. 142. Tribe vi. Asilici. Asilus crabroni- 



Tribe x. Bombyliarii. Bombylius major, f. 1 47. Tribe 

 xi. Vesiculosa. Henops marginatus, f. 148. 



FAMILY III. NOTACANTHA. 



Rostrum generally membranous, short, concealed, ex- 

 cept the terminal lips ; sucker of two pieces ; in others 

 long, syphon shaped, and concealed by a produced beak, 

 which supports the antennae ; terminal joint of antennae, 

 with many rings ; wings resting on the body, and pro- 

 vided with a central radiated ariola. Tribe i. Xylo- 

 phagei. Beris violaceus, pi. 29, f. 149. Tribe ii. Stra- 

 tiomydes. Stratiomys cliamcdeon, f. 150. 



FAMILY IV. ATHERICERA. 



Sucker consisting of two or four pieces, the two con- 

 tiguous ones provided with palpi ; retracted within the 

 sucker into a furrow of the proboscis. Tribe i. Syr- 

 phiae. ^Syrphus obscurus, pi. 29. f. 151. Tribe ii. Co- 

 nopsarise. Conops macrocephala, f. 152. Tribe iii. 

 (Estrides. (Estrus Bovis, f. 153. Tribe iv. Muscides. 

 Musca Vomitoria, f. 1 54. 



SECTION II. 



Proboscis consisting of two seta?, emerging from the 

 buccal cavity, covered by two plates or palpi, instead of 

 a bheath. 



FAMILY V. PUPIPARJE. 



Tribe i. Coriacejr. Hippobosoa equina, pi. 29, f. 1.55. 

 Tribe ii. Phthyromyiae. Nycteribia vesper tilianis, f. 1 56. 



DESCRIPTION OF EXTERNAL PARTS OF 



INSECTS. 



PLATE XXVI. 



THE HEAD AND ITS EXTERNAL ORGANS. 



The Head furnishes the most distinctive characters of 

 insects. It is exceedingly varied in its general form, as 



well as in its several parts. The most important of these 

 are the mouth, antenna, and eyes. The head of a Dipte- 

 rous insect is represented, figure 22, with all its appen- 

 dages ; but the head, independently of these is confined 

 within the limits of a a f. 22, 25. 



Mouth. This organ is very complicated, and subject 

 to great diversity of form, and construction, admirably 

 adapted to the nature of its food. It consists of six parts, 

 the labrum, mandibles, mamllcB, palpi, laMum, and men- 

 turn. Labrum, or upper lip, figs. 22, 23, 25, e, e, e. Man- 

 dibles, f. 25, k, k. Maxillae, f. 24, i. Palpi, f. 22, 23, 24, 

 25, b, b, b, b, b, and f. 29, b. Labial lobes, f . 22, 23, 25, g, 

 g, ff. Menlum, f. 29, a. Proboscis, f. 29, b. Linyua or 

 tongue, f. 29, c. 



Antennae. Horn -like processes consisting of several 

 joints ; considered by some naturalists as organs of 

 touch, and by others, organs of hearing, f. 24, 25, d, d. 

 Nasus or nose, f. 22,/ Eyes, f. 22, 1, 1. Neck, f. 22, h. 



The Thorax and its several divisions; f. 26. Collar, or 

 prothoracic seutellum, f. 22, 26, m, m. Prcescutum, f. 26, 

 n. Scutum, o. Seutellum, p. Metathoradc Scutum, f. 26, q. 



To the thorax are attached the Wings, r, r ; the rudi- 

 mental alulae or winglets s; the base of the intermediate 

 femur t ; the balancers u ; the base of the posterior femur 

 v, and the legs. Wings, f. 25, w. Elytra, are membra- 

 nous, or horny substances which cover the wings of in- 

 sects of the order Coleoptera, f. 25, x, tr. Upper or supe- 

 rior wing of a Lepidopterous insect, f. 27. Anterior 

 margin, or costal nerve, a. Interior margin, b. Exterior 

 margin, c. Post-costal nerve, d. Anal nerve, e. Com- 

 pound ocellus^ or the discoidal cell, f. Dentate fascia, g. 



Lower or inferior wing of a Lepidopterous insect, f. 

 28. Anterior margin, a. Exterior margin, b. Interior 

 margin, c. 



The Abdomen is that part which is attached to the 

 posterior extremity of the thorax, and consists of six 

 segments or wines, to which there are never any leas 

 attached, f. 29. 



In the whole insect tribe, they are provided with but 

 six Legs: they are composed of five parts, f. 30. Coxa, 

 or haunch, is the first joint, a. 'Troclianter, or second 

 joint, b. Femur, or thigh, c. Tilria, or shank, d. Tar- 

 sus, e. This member consists of from three to five arti- 

 culate parts, among Coleopterous insects, and most 

 others. To the last of these articulations are attached 

 the claws. 



