MOSS-BUILDING CATERPILLAR. 159 



the proceedings of which are well worthy of attention. 

 They are similar, in appearance and size, to the cater- 

 pillar of the small cabbage-butterly (Pontia rapce), and 

 are smooth and bluish. The material which they use in 

 building their cocoons is composed of the leaves and 

 branchlets of green moss, which they cut into suitable 

 pieces, detaching at the same time along with them a 

 portion of the earth in which they grow. They arrange 

 these upon the walls of their building, with the moss on 

 the outside, and the earth -on the inside, making a sort of 

 vault of the tiny bits of green moss turf, dug from the 

 surface of the wall. So neatly, also, are the several pieces 

 joined, that the whole might well be supposed to be a 

 patch of moss which had grown in form of an oval tuft, a 

 little more elevated than the rest growing on the wall. 

 When these caterpillars are shut up in a box with some 

 moss, without earth, they construct with it cells in form of 

 a hollow ball, very prettily plaited and interwoven. 



Moss-Cell of small Caterpillar (BryojMla pei-la ?) 



In May last (1829), we found on the walls of Green- 

 wich Park a great number of caterpillars, whose manners 

 bore some resemblance to those of the grub described by 

 M. Reaumur. (J. E.) They were of middle size, with a 

 dull orange stripe along the back ; the head and sides of 

 the body black, and the belly greenish. Their abodes were 

 constructed with ingenuity and care. A caterpillar of 

 this sort appears to choose either a part where the mortar 

 contains a cavity, or it digs one suited to its design. 

 Over the opening of the hollow in the mortar it builds 

 an arched wall, so as to form a chamber considerably 

 larger than is usual with other architect caterpillars. It 



