60 Insect Architecture. 



the same place as each is separated from the other by a 

 laborious process that the egg which is first laid will be 

 the earliest hatched ; and that the first perfect insect, being 

 older than its fellows in the same tunnel, will strive to make 

 its escape sooner, and so on of the rest. The careful mother 

 provides for this contingency. She makes a lateral opening 

 at the bottom of the cells ; for the teeth of the young bees 

 would not be strong enough to pierce the outer wood, though 

 they can remove the cemented rings of sawdust in the interior. 

 Keaumur observed these holes, in several cases; and he 

 further noticed another external opening opposite to the 

 middle cell, which he supposed was formed, in the first 

 instance, to shorten the distance for the removal of the 

 fragments of wood in the lower half of the building. 



That bees of similar habits, if not the same species as the 

 violet-bee, are indigenous to this country, is proved by Grew, 

 who mentions, in his ' Earities of Gresham College,' having 

 found a series of such cells in the middle of the pith of an 

 elder branch, in which they were placed lengthwise, one after 

 another, with a thin boundary between each. As he does not, 

 however, tell us that he was acquainted with the insect which 

 constructed these, it might as probably be allied to the 

 Ceratina albildbris, of which Spinola has given so interesting 

 an account in the ' Annales du Museum d'Histoire Naturelle ' 

 (x. 236). This noble and learned naturalist tells us, that one 

 evening he perceived a female ceratina alight on the branch 

 of a bramble, partly withered, and of which the extremity had 

 been broken ; and, after resting a moment, suddenly disappear. 

 On detaching the branch, he found that it was perforated, and 

 that the insect was in the very act of excavating a nidus for 

 her eggs. He forthwith gathered a bundle of branches, both 

 of the bramble and the wild-rose, similarly perforated, and 

 took them home to examine them at leisure. Upon inspec- 

 tion, he found that the nests were furnished like those of the 

 same tribe, with balls of pollen kneaded with honey, as a 

 provision for the grubs. 



The female ceratina selects a branch of the bramble or 



