Popular IBtctt'onarn of &ntmatett Mature. 349 



Insect, and may be numbered among the 

 most singular in the whole class of Insects. 

 From the Pupa or Chrysalis at length emerges 

 the Insect in its complete or ultimate form, 

 from which it can never change, nor can it 

 receive any further increase of growth. 



Hence there are three periods in the life of 

 an insect, more or less distinctly marked by 

 corresponding changes in the form, power, 

 and habits. In the first, or period of infancy, 

 an insect is technically called a larva, a 

 word signifying a mask, because therein its 

 future form is more or less masked or con- 

 cealed. This name is not only applied to 

 grubs, caterpillars, and maggots, and to other 

 insects that undergo a complete transforma- 

 tion, but also to young and wingless grass- 

 hoppers, and bugs, and indeed to all young 

 insects before the wings begin to appear. 

 In this first period, which is generally much 

 the longest, insects are always wingless, pass 

 most of their time in eating, grow rapidly, 

 and usually cast off their skins repeatedly. 

 The second period, wherein those Insects that 

 undergo a partial transformation, retain their 

 activity and their appetites forfood, continue 

 to grow, and acquire the rudiments of wings, 

 while others, at this age, entirely lose their 

 larva form, take no food, and remain at rest 

 in a deathlike sleep, is called the pupa 

 state, from a slight resemblance that some of 

 the latter present to an infant trussed in 

 bandages, as was the fashion among the 

 Romans. The pupae from caterpillars, how- 

 ever, are more commonly called chrysalids, 

 because some of them, as the name implies, 

 are gilt or adorned with golden spo_ts ; and 

 grubs, after their first transformation, are 

 often named nymphs ; the reason for which 

 is not very obvious. At the end of the second 

 period Insects again shed their skins, and 

 come forth fully grown, and (with few ex- 

 ceptions) provided with wings. They thus 

 enter xipon their last or adult state, wherein 

 they no longer increase in size, and during 

 which they provide for a continuation of their 

 kind. This period usually lasts only a short 

 time, for most Insects die immediately after 

 their eggs are laid. Bees, wasps, and ants, 

 however, which live in society, and labour 

 together for the common good of their com- 

 munities, continue much longer in the adult 

 state. 



Insects possess some particular parts which 

 are not to be found in any of the larger 

 animals : among these are the antennce before 

 mentioned, which are those processes or 

 jointed bodies situated on each side the head. 

 They differ extremely in the different tribes 

 of Insects, and are found to constitute one of 

 the most convenient parts to fix upon in the 

 distribution of Insects into genera and 

 species. It is therefore necessary slightly to 

 enumerate some of them : Antenna setacea, 

 or setaceous antenna; bristle-shaped, or 

 growing fine and sharp at its termination ; 

 antenna Jiliformitt, or thread-shaped, being of 

 equal size throughout: antenna monili for mis, 

 or moniliform ; each joint being globular, or 

 nearly so : antenna, clavata, club-shaped ; 

 having a knob at the top, as in the major 

 part of Butterflies: antenna fissilis, or fissile; 

 one which is split or divided at the tip into 



veral lamellae or flat separations : antenna 

 pectinata, or pectinated; one which is divided 

 along each side into numerous processes in 

 such a manner as to resemble the teeth of a 

 comb : antenna barbata, or bearded ; one 

 which is slightly feathered, either on one or 

 both sides, with fine lateral fibres or hairs : 

 antenna pcrfoliata, perfoliate ; the joints of 

 a flattened and circular shape, with the stem 

 or body of the antenna passing through them, 

 as in the leaves of some plants, in which the 

 stem seems to pass through them. Another 

 part peculiar to Insects consists in a pair or 

 two of short jointed processes proceeding 

 from the mouth : these are termed palpi, or 

 feelers, which in some Insects are very con- 

 spicuous, but not in all. The mouth in 

 Insects is generally situated at the lower part 

 of the front, and varies much in structure in 

 the different orders. In some it is furnished 

 with very strong jaws, often notched or 

 serrated on the inner side into the appearance 

 of teeth, and which always meet horizontally; 

 in others the mouth consists of a tube or 

 instrument for suction, either simple, or 

 guarded by various kinds of appendages. 

 The eyes in Insects are commonly situated 

 on each side of the head, and are two in 

 number ; but in some Insects, as in Spiders, 

 there are six or eight. In most of the Insect 

 tribes the eyes may be considered as com- 

 pound, the cornea presenting when viewed 

 with a microscope the appearance of an in- 

 finite number of separate convexities, like so 

 many real convex lenses. There are also 

 on the heads of many Insects three small, 

 smooth, lucid globules resembling so many 

 separate eyes, placed on the top of the head, 

 between or above the lateral ones : these 

 Linnaeus distinguishes by the title of stem- 

 mata ; they are also called ocelli. The body 

 in the major part of Insects is divided into 

 the thorax or upper part, and the abdomen 

 or lower part. In many of the Beetle tribe 

 the back of the thorax is distinguished by 

 a small triangular piece or division, situ- 

 ated at its lower part, between the junc- 

 ture of the wing-sheaths: this triangular 

 part is called scutellum, or the escutcheon. 

 The under part of the thorax is called the 

 breast, or pectus, and in this the sternum is 

 frequently distinguishable. The abdomen 

 is marked into transverse sections, and the 

 last joint terminates in the tail. The wing- 

 sheaths or shelly coverings, in the Beetle tribe 

 and some others, are termed elytra. The 

 name of the orders into which Insects are 

 divided, as Colcoptera, Hymenoptera, Dip- 

 tera, Neuroptera, &c., have reference chiefly 

 to the number ana nature of their wings ; 

 but as the definitions will be found under 

 their respective names, we need not here 

 repeat them. 



In the Introductory Letter to "Kirby and 

 Spence's Entomology," the beauties of the 

 Insect world are thus graphically pour- 

 trayed : "Insects, indeed, appear to have 

 been Nature's favourite productions, in 

 which, to manifest her power and skill, she 

 has combined and concentrated almost all 

 that is either beautiful and graceful, in- 

 teresting and alluring, or curious and sin- 

 gular, in every other class and order of her 



