SPINNING CATERPILLARS. 327 



When it had completed its growth, it began to spin, 

 but in a very awkward manner— attaching threads, 

 as if at random, to the bits of pollen which re- 

 mained undevoured, and afterwards tumbling about 

 to another part of the box, as if dissatisfied with 

 what it had done. It sometimes persevered to spin 

 in one place till it had formed a little vaulted wall ; 

 but it abandoned at the least three or four of these 

 in order to begin others, till at length, as if com- 

 pelled by the extreme urgency of the stimulus of its 

 approaching change, it completed a shell of shining 

 brown silk, woven into a close texture. Had the 

 grub remained within the narrow clay cell built for 

 it by the mother-bee, it would, in all probability, not 

 have thus exhausted itself in vain efforts at building, 

 which were likely to prevent it from ever arriving at 

 the perfect state— a circumstance which often happens 

 in the artificial breeding of insects. This bee, how- 

 ever, made its appearance the following spring. 



Beside silk, the cocoons of many insects are 

 composed of other animal secretions, intended to 

 strengthen or otherwise perfect their texture. We 

 have already seen that some caterpillars pluck off 

 their own hair to interweave amongst their silk : 

 there are others which produce a peculiar substance 

 for the same purpose. The lackey -caterpillar ( Clisio- 

 campa neustria, Curtis) in this manner lines its 

 cocoon with pellets of a downy substance, resem- 

 bling little tufts of the flowers of sulphur. The 

 small egger, again (Eriogaster lanestris, Germar), 

 can scarcely be said to employ silk at all, — the 

 cocoon being of a uniform texture, looking, at 

 first sight, like dingy Paris-plaster, or the shell 

 of a pheasant's egg, but upon being broken, and 

 inspected narrowly, a few threads of silk may be 

 seen interspersed through the whole. In size, it is 

 •J. R. 



u 2 



