SERICORIDAL -PEN THIN A . 365 



broad, and with their cilia smoky brown. Female similar, 

 but often a little smaller and blackei". 



Underside of the fore wings pale smoky brown ; costa and 

 hind margin dotted or dusted with white. Hind wings 

 leaden-white. 



Usually not variable, but upon hills in the Midlands it 

 has sometimes the pale portion of the fore wings unusually 

 white ; while in Scotland the dark portions are often much 

 blackened. Very rarely a creamy-white variety has been 

 noticed ; Mr. Thurnall records one such in Essex. 



On the wing from the end of May till July. 



Larva sluggish, short and plump ; bright green, raised 

 dots distinct, shining black, furnished with short hairs; head 

 and dorsal plate shining black ; anal plate either black or 

 green. 



April to June on blackthorn, eating out the heart of a 

 young shoot, and living within the drawn-together terminal 

 leaves. When full grown it abandons this shoot and twists 

 or folds a leaf — often of some other plant growing beneath — 

 into a small neat chamber fastened at the edges with white 

 silk. Treitschke states that it feeds on all the species of 

 Primus, Cratccfjiis and FiOmi. With us it seems to confine 

 itself to blackthorn, plum, and occasionally hawthorn. 



Pupa dull black; abdomen well furnished with spines; in 

 the neatlj- formed chamber already I'eferred to. 



A lively, active insect, hiding during the day either in or 

 under blackthorn bushes, especially those growing in hedges 

 — perhaps in almost every such bush or hedge in England, 

 Ireland and Wales — in Scotland apparently occurring 

 throughout the Lowlands, though not everywhere common, 

 and, I think, not recorded beyond Aberdeen. Common 

 throughout Central and Southern Europe, and in Sweden ; 

 also Asia Minor, and Persia. 



