Sept., I9i6.] ACKERMAN : CaRPENTER-BeeS OF U. S. 217 



the mandibles, whose teeth are two in number, located at the apex ; 

 labrum consisting of one blunt lobe, rather large and triangular in 

 shape; clypeus well punctured, a little convex in its superior half, a 

 deeply concaved, shining, impunctate area along its lower margin, 

 which is dark red in many specimens, the longitudinal carina barely 

 evident ; lateral foveote and frontal grooves very deep and promi- 

 nent; frontal shield iridescent, very convex; its sides sloping greatly; 

 frontal carina very large and blunt (more prominent than in vir- 

 ginica), so that the median ocellus appears sunken, posterior ocelli 

 carinated in front, a small circular pit behind each ; antennae black, 

 eyes not large, widely separated ; vertex and cheeks with a strong, 

 bluish purple color, punctures larger and fewer on face, hairs entirely 

 dark. 



Thorax black on disk, changing to blue, green and purple on sides 

 and beneath ; pilosity very dense, yellowish white on top, except the 

 disk and on sides, black below ; scutellum blue to green, well punc- 

 tured; post-scutellum small and little punctate. 



Abdomen elongate, olive green with blue reflections ; punctation 

 fine and close on first segment, otherwise sparse ; yellowish white 

 hairs on first segment, a patch of them on sides of segments five and 

 six, and a few scattered ones on sides of intervening segments, hairs 

 elsewhere black ; epipygium very large, spines small. 



Wings fusco-hyaline with a violet tint, darker at the apex, tegulte 

 brownish black. 



Legs blue, purple, sometimes a little greenish, hairs black, brown 

 on inner side of fore tarsi. Tibial scale with anterior tooth narrow 

 and very pointed, posterior one wider and pointed, the two teeth of 

 equal length ; form not as elongate as in virginica, being almost as 

 wide as it is long. 



Male. — Difl:'ers as follows: Head yellow on labrum, clypeus, frontal 

 shield; in some specimens a little on the lateral areas of the frons 

 between the clypeus and eyes as high as the insertion of the antennae 

 and a small spot at the base of the mandibles ; color otherwise black 

 with bluish purple on the vertex and cheeks ; head not as wide as in 

 the other sex, face more narrowed; hairs of head yellowish white 

 on cheeks and vertex, some scattered patches on frontal shield, be- 

 tween insertion of antennse and between the posterior ocelli ; mandi- 

 bles smaller, depression at base not so deep ; labrum a little wider ; 



