132 HYMENOPTERA. 



Xylocopa, the Carpenter-bee, is "the largest and most bulky 

 of all known baes," but less hirsute than Bombus, while the 

 basal joint of the labial palpi is almost four times as long as 

 the second ; and the maxillary palpi are six-jointed, the mouth- 

 parts being very highly organized. The larva of X. Virginica 

 (Plate 4, Fig. 3, adult ; Fig. 4, larva ; Fig. 5, nest) is slenderer 

 than that of Bombus, the body tapering more rapidly towards 

 each end. 



The power of boring the most symmetrical tunnels in solid 

 wood reaches its perfection in the large Virginian Carpenter- 

 bee (Xylocopa Virginica). We have received from Mr. James 

 Angus, of West Farms, N. Y., a piece of trellis for a grape- 

 vine, made of pine wood, containing the cells and young in 

 various stages of growth, together with the larvae and chrysa- 

 lids of Anthrax sinuosa (Plate 4, Fig. 6, larva; Fig. 7, pupa), 

 a species of fly parasitic on the larva of the bee, and which 

 buries its head in its soft bod} T and feeds on its juices. 



Mr. Angus thus writes us regarding its habits, under date of 

 July 19 : "I asked an intelligent and observing carpenter yes- 

 terday, if he knew how long it took the Xylocopa to bore her 

 tunnel. He said he thought she bored about one-quarter of an 

 inch a day. I don't think myself she bores more than one- 

 half inch, if she does that. If I mistake not, it takes her 

 about two days to make her own length at the first start ; but 

 this being across the grain of the wood may not be so easily 

 done as the remainder, which runs parallel with it. She always 

 follows the grain of the wood, with the exception of the en- 

 trance, which is about her own length. The tunnels run from 

 one to one and a half feet in length. They generally run in 

 opposite directions from the opening, and sometimes other gal- 

 leries are run above the first, using the same opening. I 

 think they only make new tunnels when old ones are not to be 

 found, and that the same tunnels are used for many years. 

 Some of the old tunnels are very wide. I have found parts of 

 them about an inch in diameter. I think this is caused by 

 rasping off the sides to procure the necessary material for con- 

 structing their cells. The partitions are composed of wood- 

 raspings, and some sticky fluid, probably saliva, to make it 

 adhere. 



