MEANS AND DEFENCE OF CATERPILLARS. 193 



selves a snug nest of silk, such as the caterpillars of 

 the brown-tail moth (Porthesia auriflua), and those 

 of the mallow butterfly (Hesperia malvce). But there 

 are others which are provided with no extraneous 

 covering, farther than the occasional shelter they may 

 obtain by crawling under withered leaves, the copings 

 of walls, or the bend of a branch. Among these 

 some are thickly covered with hair, of which we have 

 an instance in the caterpillar of the great tiger moth 

 (Jlrctia caja y STEPHENS), whose mode of rolling it- 

 self up into a ball we have already described; but a 

 more remarkable example occurs in the caterpillar of 

 the drinker moth (Odonestis potatoria, GERMAR.), 

 whose very feet are covered with fine shaggy dow\ 

 It is this, no doubt, which preserves it from becoming 

 torpid during winter,; and as it feeds on grass, it can 

 always procure food during the severest weather. 

 When a fine sunny day chances to break in upon the 

 gloom of winter, this pretty insect may be often seen 

 stretched at its full length on a low twig, or the with- 

 ered stem of a nettle, basking in the sunshine with 

 apparent delight. We kept one of them in our study 

 during the winter of 1827-8; and it continued to feed 

 sparingly till February, when, owing to neglect, it un- 

 fortunately died. 



There are several other caterpillars, however, 

 which live during the winter, in a no less exposed 

 manner, without being provided with any covering of 

 hair; though some of these, we may remark, do not 

 continue to feed, but become wholly or partially tor- 

 pid, such as the caterpillar of the magpie moth 

 (Jlbraxas grossulariata). Of this species we have 

 observed numbers, about as thick as a crow-quill, re- 

 maining in the same position for weeks together, and 

 never moving, except when some very considerable 

 change of temperature, either colder or hotter, took 

 place. They do not seem to select the warmest places 



* J. R. 



VOL. VI. 17 



