THE CANADIAN ENTOMOLOGIST. 247 



Sides of mesonotum reticulated ; cell III, .,.., pointed on costa r. 



i. Larger, greener; antennse, tegulse and legs darker confusa. 



Smaller, more brassy ; antennae, tegulae and legs paler similis. 



Males. 



Ventral segment 4 not emarginate, greenish pura. 



Ventral segment 4 emarginate, not greenish 1. 



1. Larger, greener ; antenna;, teguUe and legs darker confusa. 



Smaller, more brassy; antennae, tegulse and legs paler similis. 



Lasioglossum, Curtis (Type Melitta xdnthopus, Kby.). 



Females. 

 Metathorax sharply truncate, the posterior face with sharp 



edge fuscipenne. 



Metathorax rounded posteriorly, no distinct posterior face 1. 



1. Clypeus less produced ; mesonotum more shining ; metathorax more 



rugose, more shining, the edge more salient Forbesii. 



Clypeus produced ; mesonotum and metathorax smooth and 



opaque coriaccum. 



Males. 

 Face subquadrate ; apex of one mandible reaching base of the other ; 



tarsi dark ... coriaceum. 



Face narrowed below; apex of one mandible reaching the middle of 

 the other ; tarsi whitish Forbesii. 



Evylaeus, gn. nov. (Type Halictus arcuatus, Rob.). 



Females. 



Abdomen with pubescent fasciae interrupted or wanting 2. 



Abdomen with pubescent fasciae continuous ; metathorax coarsely 



rugose 1 . 



1. Metathorax sharply truncate; hind spur with long distinct teeth; 



segment 1 iaipunctate truncalus. 



Metathorax a little rounded behind ; hind spur with teeth shorter, 

 more oblique, less distinct; segment 1 finely punctured .. arcuatus. 



2. Hind spur pectinate, with numerous fine, rather long, 



teeth pect hiatus. 



Hind spur with 4 or 5 distinct teeth 3. 



3. Metathorax without an enclosed space 5. 



Metathorax with an enclosed space 4. 



4. Enclosure subtriangular ; metathorax elsewhere densely pubes- 



cent nelumbonis. 



Enclosure semicircular ; metathorax bare or nearly so . . . .pectoral is. 



