INSECTA. 433 



Of their external Surface. — The caterpillar in some is smooth, as that 

 of the silk-moth, and probably of most of the moth-kind. In others it 

 is extremely rough and hairy ; pencils of hair coming out from the skin, 

 as in many of the butterfly-kind. They are of various colours, both 

 those that are smooth and those that are rough. The maggot has a 

 smooth skin, and is commonly of a light cream colour. 



They are all, I believe, produced from an egg ; but how far this egg 

 is similar to that of a fowl I know not. 



Of the Disposal of their Eggs. — The whole concern of the female about 

 the egg is, in some species, the proper soil for incubation. Some, as 

 butterflies and moths, choose vegetables. Others choose living animals, as 

 the bott [CEstrus Equi] in the stomach of the horse, the CEstrus Bovis in 

 the backs of cattle, the CEstrus nasalis in the nose of the deer, the (Estrus 

 Tarandi in the back of reindeer, the CEstrus [Gastrus~\ hamiorrhoidalis 

 in the rectum of horses, the (Estrus Ovis in the nose and frontal sinuses of 

 ruminating animals, especially sheep, the little insect in Mexico called 

 'Migna,' [Chigoe?] under the skin, the Vena medinensis 1 in the flesh. 

 Others, as several flies, select dead animal matter which is moist and in 

 a state of putrefaction : others, as the moth called [Tinea tapezata, 

 Fabr.], and several Dermestides, select dry animal matter ; and others, 

 as the gnat, choose stagnant water. Some, as the ant, lay their eggs in 

 common earth, without any formation of it into a nidus; while others, 

 as all of the bee-kind, the Scarabceus, &c, are at great pains to make 

 proper places for the eggs. 



Some insects may be said to lay their eggs in society, others to be 

 solitary, while there are a few of the mixed kind. Of the first is the 

 bee and the wasp ; of the second are most of the butterflies, moths, 

 beetles, &c. ; of the mixed kind are those, as the common fly, that lay 

 their eggs as may be most convenient, one, two, or a hundred in one 

 place. The silk- worm moth lays its eggs as it goes along upon the parts 

 where it chooses to lay them. 



Of the Time of Laying and Hatching. — Some, as the silk- worm and the 

 black-beetle [Geotrwpes~\, lay their eggs in the months of August and 

 September, and these are not hatched until the summer following ; the 

 greater number, as most flies, the little white moth with a brown tail 

 [Porthisia chrysorrhosa], the bee, wasp, gnat, &c, lay eggs which are 

 hatched in the same summer. 



Of their Economy when hatched. — When hatched, many, as the 

 Phalcenos, spin a network or covering for themselves, where they retire 

 in the evening. 



1 [Filaria medinensis, or ' guinea-worm,' an entozoon, not a larva.] 

 VOL. II. 2 F 



