CARPENTER-BEES. 51 



insect being older than its fellows in the same tun- 

 nel, 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 saw- 

 dust in the interior. Reaumur observed these holes, 

 in several cases ; and he further noticed another ex- 

 ternal 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 

 Wi the lower half of the building. 



That bees of similar habits, if not the same spe- 

 cies as the violet bee, are indigenous to this country, 

 is proved by Grew, who mentions, in his ' Rarities 

 of Gresham College,' having found a series of such 

 cells in the middle of the pith of an old elder branch, 

 in which they were placed lengthwise, one after an- 

 other, 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 albilabria, of 

 which Spinola has given so interesting an account 

 in the ' Annales du Muse'um 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 perfo- 

 rated, and that the insect was in the very act of exca- 

 vating a nidus for her eggs. He forthwith gathered 

 a bundle of branches, both of the bramble and the 

 wdd-rose, similarly perforated, and took them home 

 to examine them at leisure. Upon inspection, he 



