72 INTRODUCTION. 



and in others issue in tufts from rounded tubercles 

 arranged in a certain order. These tufts sometimes 

 assume a very peculiar form, especially in the larvae 

 of Tussock-moths (Qrygia, Laria, &c.) and a few 

 others. Two long fascicles stand out from behind 

 the head and project forwards, the hairs of which 

 are dilated at the point in such a manner as to make 

 them resemble a painter's brush. A similar fascicle 

 springs from the hinder extremity and is directed 

 backwards, and along the back there is a series of 

 short wedged-shaped tufts of equal length formed 

 by thick-set parallel hairs. These elongated tufts 

 are often rendered still more conspicuous by being 

 of a different colour from the other hairs ; the latter 

 also vary greatly in their tints, which are often 

 mingled and diversified so as to produce a very 

 ornamental effect. When the hairs are long and 

 thickly set, as is often the case, they form a very 

 efficient clothing, and tend to save the larva from 

 injury when it happens to fall ; they likewise seem, 

 at least in many cases, to be organs of touch, 

 for the slightest impression upon them produces 

 movements in the animal which indicate that it is 

 felt. Lyonet has shown that those of the Goat- 

 moth caterpillar are partly hollow, and set in a 

 scaly ring somewhat elevated above the skin, through 

 which the root communicates with a soft integu- 

 ment upon which the nerves form a reticular tissue, 

 a structure which renders it highly probable that 

 they perform the function just alluded to. 



With so much difference in the form, members, 



