752 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



Male with the second ventral abdominal segment subtruncate ; 

 third antennal joint about one-half as long as the fourth; flagel 

 stramineous ; clypeus bearded. 



Occurs all over the State in June, July, and August. Has been 

 taken at Branf ord, Sachem^s Head, Prospect, and Putnam. 



Dianthidium Cockerell. 

 The French call the species of this genus " resiniers," 

 because they use resin in cementing fragments to form their nests. 



Key to Species. 



Females. 



Vertex black; face, clypeus, thorax, legs, and abdomen macu- 

 lated with yellow; first to fifth dorsal abdominal segments 

 each with a lateral transverse fascia which is indented 

 posteriorly except on first segment; first segment with an 

 additional median transverse fascia; apex of clypeus 

 simple simile 



Vertex with a transverse reddish or yellowish band along its 

 posterior margin; face with a stramineous portion that is 

 partly yellowish stramineous, partly reddish stramineous 

 or yellow, on each side of the black, partly yellow clypeus; 

 rest of head black; thorax with yellowish or reddish 

 maculae; legs entirely, or almost entirely, yellowish or red- 

 dish; first dorsal abdominal segment with a yellow or red- 

 dish mark on each side, second with an interrupted fascia, 

 third, fourth, and fifth divided into three parts by a nearly 

 quadrate yellow mark on each side notatum 



Males. 



Sixth dorsal abdominal segment with an abbreviated, im- 

 perfect, median raised line just at apex of segment; its 

 apical margin not toothed; seventh in form of an oblong 

 plate, which is prolonged to form an apical, short, rounded 

 production of apical margin of segment, which is emargin- 

 ate on each side of this apical process; maculated like the 

 female; in addition, clypeus all yellow, mandibles 

 maculated, and seventh dorsal abdominal segment mostly 

 yellow simile 



Sixth dorsal abdominal segment and other parts maculated 

 essentially as in the female of notatum .notatum 



D. simile Cresson. 



Farmington ? 



