272 INSECTS AND MAN 



CLOTHES MOTHS 



The mention of moths, as household insects, will at once 

 suggest the clothes moths, which have earned for themselves 

 a place in the front rank of destructive insects. The true 

 clothes moth is Tinea pellionella, but allied species, in the 

 shape of Tinea biselliella and Tinea tapetzella, are also de- 

 structive. Pellionella is a greyish-yellow moth, measuring 

 about half an inch across its expanded wings, on the middle 

 of which there are a few indistinct spots. That these in- 

 sects have been known from Biblical times is shown by two 

 references, in Job and Isaiah respectively, to moths eating 

 clothes. The female lays her eggs on some material which 

 will furnish the larvae with food, woollen goods, carpets, 

 furs, and feathers are most frequently attacked. The eggs 

 are so small as to be scarcely visible to the naked eye, and 

 from them the dull white larvae emerge. The first duty of 

 this caterpillar is to build for itself a case in which to live, 

 and of the larva Pliny says, " It is clad in a jacket, gradually 

 forming for itself its own garment, like a snail in its shell, 

 and when this is taken from it, it immediately dies ; but 

 when its garment has reached its proper dimensions it 

 changes into a chrysalis, from which at the proper time 

 the moth issues." The description is wonderfully accurate, 

 but it is of interest to add that the case must perforce be 

 enlarged, from time to time, to keep pace with the larval 

 growth. While still within the case, the larva makes a 

 slit down one side and inserts a triangular gore of new 

 material, the operation is then repeated on the opposite side. 

 If the larva be moved periodically to materials of varied 

 colour, its case will present a mixed coloration, correspond- 

 ing to the materials of which it is comprised. Additions to 

 the length of the case are made at either end. When full 

 grown, the larva usually attaches its case to the material on 

 which it has been feeding. Pupation takes place within the 

 case, and the adult moth appears three weeks later. 



