SINGULARLY CONSTRUCTED COCOONS. 



221 



roimd its body ; these are in no ways employed in the con- 

 struction of the cocoon itself, and seem only to be erected 

 to defend the larva whilst working. Near to one end of 

 this inclosure, the larva now commences its cocoon in the 

 manner represented in the above figure. 



The mode in which the ridges of this cocoon are formed 

 with perfect regularity, is indeed inconceivable. Some idea 

 may, however, be obtained of it from the two following 

 figures. 



Here m, i, e, represent three longitudinal ridges, and m i, 

 I E, the intermediate space ; the caterpillar, commencing at 

 E, extends a thread to h, from h to i forming an angle, from 

 I it then proceeds to k, and from k to h, forming another 

 acute angle, and then from h to y, and y to i, forming 

 another obtuse angle. It then proceeds in the same manner 

 from I to M, as it had from E to i, and in this manner pro- 

 ceeds until it has nearly formed half its case, when turning 

 round it begins at the other end, and at length unites the 

 two halves together, "thus inclosing itself," as Lyonnet 

 says, " en une jolie cage " of net-work, which occupies only 

 half an hour in the construction, but which is subsequently 

 rendered much more firm by a strong layer of silk within. 



The other instance which I propose to notice, is that of 

 another small moth {Microsetia ruficapitella), the lai-va of 



u3 



