OBSERVATIONS ON BRITISH TINEINA. 105 



The transformations of the species of this group being still 

 much enveloped in doubt and obscurity, I have carefully 

 studied and delineated all that seemed likely to be serviceable 

 in enabling one to recognize with facility the different stages 

 of this Adela. 



^' The case appears to be cut out of the dead and dried 

 leaves of the beech ; it is open at both ends and slightly 

 fastened at the sides ; it is composed of pieces of leaves placed 

 one upon the other, and half-opens like the shells of some 

 bivalves. It is very large in proportion to the size of the 

 larva. As I have only hitherto observed these cases in 

 spring, after hybernation, it would be very interesting to learn 

 the habits of the young larvae. These larvae hybernate when 

 full grown, but they eat a little for a few days, and easily 

 climb up the stout branches to reach the buds ; they prefer 

 those of the beech and hazel. 



" Preparatory to assuming the pupa state, the larva spins 

 a solid cocoon in the interior of its case ; the case then be- 

 comes rounder, and by this difference of form one can easily 

 distinguish whether the case contains a larva or a chrysalis." 



The whole of the details are too long for extraction here 

 (see Ann. Ent. Soc. Beige, iv. pp. 95—99, Planche II.). 



At the time the alDOve paper was read, Dr. Breyer, who 

 has also devoted his attention to this group, observed, — 



" I can fully confirm, with my own experience, the obser- 

 vations of M. Becker. I know these bivalve-cases, and have 

 collected a considerable number of different forms since the 

 beginning of the year. The simple bivalves, that is, those 

 in which each valve is cut directly out of a dead leaf, belong 

 to the genus Incurvaria. The compound bivalves, that is, 

 those in which each valve is formed of a series of pieces 

 added one after the other, indicate the genera Nemopliora 

 and Adela. But these statements yet require to be carefully 



