THE PYRALIDINA. 1 39 



The Bordered Pearls, the Mother of Pearls, the lonsr-wineed 

 Pearls, and the small Magpie are well-known moths which belong 

 to the genus Botys. They have long trunks and very pretty wings. 

 The caterpillars are rather long and are extremely rapid in their 

 movements. They twist up the leaves with a few silken threads 

 and make safe hiding places, the small Magpie choosing the sting- 

 ing nettle for its particular habitation. Its membranous legs are 

 particularly adapted for walking on plain surfaces, but not for 

 climbing. Everybody may recognise them, because when they are 

 disturbed they wriggle about in the most extraordinary manner. 



Of all the Lepidoptera the Hydrocampidcs are perhaps the 

 most extraordinary so far as their methods of life are concerned. 

 The moths fly and enjoy the air as much as any others, and 

 cannot be distinguished from those whose caterpillars live on 

 dry land. Their breathing apparatus is like that of other 

 moths, and they have the habits of the other night-flyers. But 

 the caterpillars live in the water and respire in two manners. 

 In some kinds of the Hydrocanipidcs the caterpillars live in the 

 water, surrounded by a great bubble of air, and others positively 

 have gills or branchiae, and are surrounded and bathed by water. 

 This is a most extraordinary fact, for the moths which are pro- 

 duced by metamorphosis from these caterpillars, resemble each 

 other to a great extent, and it shows how slight the distinction 

 may be between aquatic and air-breathing animals, and how nearly 

 the origin of the separate conditions may be allied. The gills 

 are in the shape of filaments, like those of the larvae of the 

 caddis flies, but there is one kind {Parapojiyx) whose larvae have 

 large branchiae and also spiracles. Its pupa is found in a cocoon 

 amongst leaves under water, but it does not appear at present 

 certain how the moth gets out of the chrysalis case without 

 drowning itself 



There is a common species in France which lives upon the 

 pond weed. Whilst in the caterpillar state it cuts two pieces 

 of leaf and fashions them so that they become oval in shape 

 and nearly equal in size. It unites them by their margins, sew- 

 ing them as it were with a little silk, and leaving an opening 

 for its head and the first segments of the body. It drags 

 this house about under water, but sometimes leaves it for a 



