42 



NATURAL HISTORY. 



[CH. H 



the body except the respiratory spiracles, the resul! 

 of which was, that although kept in the ordinary 

 temperature, the exckision of the perfect insects 

 was delayed for some weeks. 



But there are other circumstances connected with 

 the irregular appearance of insects in their perfect 

 state, which it is impossible to account for upon the 

 same principles as those observed in the preceding 

 experiments: — these are, first, the circumstance of 

 some insects remaining for one or more years in the 

 chrysalis state, while others of the same species, 

 reared in a precisely similar manner, are evolved 

 at the proper season ; and, secondly, the irregulai 

 appearance of certain insects. 



" The parental cares of nature," observes Mr. 

 Haworth, in his account of the small eggar moth 

 {Eriogaster lanestris), " are extended towards this 

 poor insect in a very extraordinary and interesting 



