138 TRANSFORMATIONS OF INSECTS. 



are classified by some naturalists amongst the Bonibycina, which 

 we have already noticed, and in one small family, the Hydro- 

 campidcu, the caterpillars live in the water, and undergo their 

 metamorphosis there, one species of it being furnished with 

 branchiae (" fins"). The Meal Moth, Asopia farinalis, which is 

 very common in houses, is a small moth with reddish-brown 

 wings, with their centres patched with fawn or grey colours. Its 

 caterpillar looks as if it were varnished, and has its membranous 

 legs very slightly developed. It has the curious taste of dis- 

 regarding the crisp leaves of the garden, and of liking pieces of 

 straw or corn, or even animal matter. These insects undergo 

 a regular metamorphosis inside little silken cocoons, and the 

 moths have a rudimentary trunk, and do not take any nourish- 

 ment. Another moth, the Tabby, Aglossa pinguinalis, is also 

 found in houses and stables. The caterpillar is of a uniform 

 dark brown, with its head and front legs of a darker tint, and 

 it will have nothing whatever to do with the usual food of 

 Lepidopterous larvae. It has a fancy for greasy horse-cloths, 

 and grease in any form ; moreover, its structures are evidently 

 suited for its love of fatty matters. The caterpillar sticks 

 itself into the grease bodily, and without danger of being 

 suffocated, for its spiracles are covered by folds of the out- 

 side skin, which prevent the grease and fat from blocking 

 them up. It is always interesting and instructive to notice 

 how Nature provides for the well-being and safety of living 

 things existing under extraordinary circumstances, and it is 

 important to remember that horse-cloths, grease, and kitchen 

 fat are productions of a more or less recent civilisation, and 

 that these moths obtained their peculiarities, which always 

 descend generation after generation, after the invention of this 

 greasy nastiness. They are either new species which have 

 become evolved from others, which led different lives before 

 horse-cloths were invented, or else they were specially created 

 to relieve the world of much fat, and things we don't care 

 about. Which of the two origins is the correct one must be 

 left to the intelligence of all the good people who, if they are 

 not very well qualified to give an opinion upon the origin of 

 species, never hesitate to do it. 



