CECETICUS. 213 



in 181 7, and found it abundant on various trees, being particu- 

 larly injurious to fruit trees in gardens. Mr. Guilding reared 

 the larvae in abundance, during several years' residence, but he 

 was much puzzled at breeding males only, for he did not think 

 of searching in the pupa-cases for the females, but imagined that 

 the female pupa had not been fully developed owing to the 

 attacks of parasites. At last, however, a specimen was un- 

 cased after the rupture of the thoracic carina, and the mystery 

 was solved. When the female has come to sexual maturity, 

 she opens the carina by the motion of her head, and prepares 

 to receive the winged male. Afterwards the female packs the 

 bottom of her pupa-case with eggs, covered with down from 

 her own body, and then dies within the case, or squeezes her 

 shrivelled body through the opening and dies outside. 



The eggs are small, round, yellow, and very numerous, and, 

 as soon as they are hatched, the larvae quit the pupa-case, spread 

 themselves over the trees, and at once begin to form their 

 cylindrical cases of scraps of wood and leaves, held together by 

 threads, and open at both ends. In these cases they move 

 about, like the larvae of caddis-flies. When young, they hold 

 the tail erect, but afterwards it is weighed down by the pressure 

 of the case. The larva is thick and fleshy, with sixteen legs, 

 the thoracic legs being unusually thick and strong. The body 

 is clothed with a few scattered hairs, and the head and three 

 thoracic segments are yellowish, varied with brown, the rest of 

 the body being of a dull livid colour. When the larva is 

 alarmed, it very rapidly closes the purse-like aperture of its 

 dwelling by means of its mandibles and fore-legs, and thus 

 remains in security, suspended only by a few threads. Fig. 

 I shows a female larva in its case ; and Fig. 2 represents the 

 same larva without its case. When it has reached its full 

 growth, it attaches one end of its case firmly to a branch by 

 strong silken threads, and having thus suspended it, the larva 



