Robertson — North American Bees. 319 



vertex; the latter with a conspicuous median tubercle reach- 

 ing from occiput nearly to anterior ocellus ; labrum short and 

 rounded, black; mandibles except base rufous, strongly 

 dentate; antennae black; the head and thorax with thin pale 

 pubescence ; rather close on collar and tubercles ; mesonotum 

 coarsely punctured, the punctures close anteriorly, sparse on 

 the disc ; metathorax, as well as the whole thorax beneath, 

 coarsely reticulated, the disc with semi-circular inclosure; 

 wings except base dusky, tegulae and nervures dark; legs 

 black, tibial spurs whitish. Length 7 mm. 



Illinois; one specimen. 



This species is distinguished from S. confertus Say by the 

 punctures of the mesonotum being not " equally close set," 

 by its entire labrum, dentate mandibles, and tuberculate ver- 

 tex, clouded wings, etc. Other specimens may not show the 

 red color of abdomen to be limited as indicated in the 

 description. 



Sphecodes davisii $. 



Black, opaque, the base of abdomen shining; head, thorax 

 and legs with rather long, whitish pubescence, more close on 

 clypeus, cheeks and thorax beneath; mandibles, except base, 

 rufous; antennae dull ferruginous beneath, short, joints in- 

 creasing in length from second to fourth ; fourth and follow- 

 ing joints subequal; mesonotum rather closely and strongly 

 punctured, with median and lateral raised lines; metathorax 

 strongly reticulated, with a semicircular inclosure ; tegulae 

 testaceous exteriorly ; wings hyaline, nervures testaceous, 

 stigma black ; legs black, apical joints of tarsi ferruginous; 

 abdomen almost impunctate at base, towards apex closely and 

 finely punctured, first and fourth segments at apex and the 

 second and third entirely ferruginous. Length 10 mm. 



Michigan ; one $ specimen. 



Dedicated to Mr. G. C. Davis, of Michio-an Asfricultural 

 College, from whom the specimen was received. No reliance 

 need be placed on the definite limitation of the red color of 

 abdomen in the description of a single specimen. This is 

 the largest male Sphecodes I have seen. 



