312 HOMES WITHOUT HANDS. 



It has well been remarked that the strength, or, at all events, 

 the weather-resisting power of a cocoon, depends upon the length 

 of time which is occupied by the insect in undergoing its trans- 

 formation, those creatures which only spend a few weeks in the 

 pupal state being content with a mere web or hammock of silk, 

 while those which pass the winter in the pupal condition make 

 habitations which are comparatively substantial. 



This rule, however, is not without its exceptions, as we find the 

 pupae of several butterflies, the common cabbage butterfly, for ex- 

 ample, merely hung against walls, etc., without any protection 

 around them. Instinct leads them to choose such spots as can 

 best afford them shelter, as every one knows who has a tool-house 

 or a summer-house in the garden, but there are many cases in 

 which no such protection can be found, and the insects are forced 

 to content themselves with the southern side of a tree-trunk, or 

 the least windy side of a paling. 



The caterpillar of. the Spurge Moth is rather prettily marked, 

 being striped longitudinally with white, red, and brown, relieved 

 with black, and furnished with some scanty tufts of hair on each 

 segment. 



One species of insect suspends the cocoon by a thread at each 

 end, so that the resemblance to a hammock is exact. This is the 

 Argyromiges autumnella, one of the minute moths called Micro- 

 Lepidoptera. The larva of this species is naked. It is a native 

 of England. 



We now pass to the enormous variety of caterpillars which are 

 popularly called Leaf-rollers, because they make their homes in 

 leaves which they curl up in various methods. 



Some use a single leaf, and others employ two or more in the 

 construction of their nests. Even the single-leaf insects display 

 a wonderful variety in their modes of performing an apparently 

 simple task. Some bend the leaf longitudinally, and merely fast- 

 en the two edges together, while others bend it transversely, fix- 

 ing the point to the middle nervure. Some roll it longitudinal- 

 ly, so as to make a hollow cylinder corresponding with the entire 

 length of the leaf, while others roll it transversely, so that the cyl- 

 inder is only as long as the leaf is wide, and a few species cut a 

 slit in the leaf and roll up only a small portion of it. 



The leaf-roller caterpillars belong to numerous species, and are 

 plentiful enough — too plentiful, indeed, to please the gardener, 



