THE CANADIAN ENTOMOLOGIST. 221 



know of one, no matter how obscure the subject or how little advance has 

 yet been made in the direction of its elucidation, 



" Hope springs eternal " in the breast of the entomologist, and patience 

 and perseverance have in him their "perfect work," until Nature relents, 

 or is caught " off guard," and the secret, so carefully hidden, is revealed. 



I am tempted to enumerate some of the discouraging circumstances 

 encountered by the biologist in this field. 



Among the Lepidoptera, a majority of the Bombycidce, Geometridce 

 and Nodiiidce adapt themselves readily to the conditions of the rearing 

 cage. They accept the food provided and make the best of it, even after 

 it has become a Httle dry, which must sometimes occur when the care- 

 taker is pressed for time. They thrive in the closer and darker air, and 

 take such exercise as they require within their narrow walls of glass and 

 wire-cloth, and when the metamorphic impulse comes they contentedly 

 weave their cocoons in the corners of their prison, or bury themselves in 

 the two or three inches of cemetarial earth in the bottom of the cage, and 

 safely pass those mysterious transformations which give to this class of 

 beings their pre-eminent interest. 



But there is a great deal of individuality, or rather, specificality, in 

 insects, and not infrequently specimens of larvae are found for which the 

 collector taxes his ingenuity in vain to provide. Not the freshest of 

 leaves, the cleanest swept earth or the most well-aired of cages will seem 

 to promote their development. They wander about the cage with an ex- 

 hausting activity that pathetically suggests a realization of their imprisoned 

 condition. They nibble languidly at their food, and aimlessly spin mats 

 of web in inconvenient places, over the cracks of the door or cover, for 

 instance, and, before long, comes the morning when they are discovered 

 dead and discolored in the bottom of the cage, and no more of them to 

 be obtained until another season. Or perhaps the cocoons are spun or 

 the transformation to pupae safely effected under ground, and the ento- 

 mologist has full confidence that in due time he will obtain the much 

 desired imago, and, when it may be expected, watches hourly for its 

 emergence, and is rewarded by the appearance of an Opliion or a swarm 

 of Tachina flies, or of some still smaller enemy, whose existence he did 

 not even suspect. 



Again, the collector may be obliged to delegate his cares temporarily 



