1897.] NATURAL SCIENCES OF PHILADELPHIA. 347 



B. Pubescence of pleura black. 



a. Pubescence of scutellum black, with a few pale hairs intermixed, 



of sides of rnetathorax black ; head strongly blue, 



atrocyanea, Ckll. 



b. Pubescence of scutellum light, with, at most, a few dark hairs in- 



termixed ; head less blue, clypeus black or almost so, 



nigrifrons, Cr. 

 (An authentic specimen from Colorado, sent me by Mr. Fox ; 



one from Colorado Springs, Colo., sent by Prof. L. Bruner; 



one from Olympia, Wash., May 25, sent by Mr. T. Kincaid.) 



Synhalonia edwardsii (Cresson, 1878). 



This is evidently common at Olympia, Wash,, and is sent in num- 

 bers by Mr. T. Kincaid. Cresson describes only the $ ; the 9 is 

 from 14 to 16 mm. long, and differs from that of S. frater by its 

 mouse-colored thoracic pubescence and by the abdominal bands, 

 which, though very Avhite, are reduced to two, on the third and 

 fourth segments, that on the third interrupted in the middle. The 

 second segment has a small white patch on each extreme side. A 

 Seattle 9 has the thoracic pubescence ochraceous as m frater, but 

 the abdominal characters remain quite distinct. One Olympia 9 

 has an interrupted band on the second segment. Within what must 

 be considered the specific limits of S. edwardsii there are, in Wash- 

 ington State, two distinct types : — 



(a.) Race latior. $ . Facial quadrangle not far from a square, sides 

 of the clypeal yellow, gradually sloping above, distance be- 

 tween the yellow and the eyes quite considerable. Olympia 

 and Seattle. 



(b.) Race angustior. $ . Face conspicuously longer than broad. 

 Sides of clypeal yellow, above squarely notched, distance be- 

 tween the yellow and the eyes extremely small ; pubescence 

 somewhat paler. 9 . Smaller, with paler pubescence, abdo- 

 men with the white bands on the fourth and fifth (instead of 

 third and fourth) segments, that on the fifth fuscous in the 

 middle, but brilliant white at the sides, a white mark on each 

 side of third, apical segment white at sides. Wings clearer. 

 Pasco. The exact data are as follows : — 



Race latior. Olympia, 18 $ , April 24, May 2, 10, 11, 17, 21, 23, 

 25 ; June 5 ; 19 9, June 1, 5, 11, 18, 19, 21, 24, 25, 29, July 

 4. Seattle, 3 $, April 17, May 3 ; 2 9 , both May 19 (T. 

 Kincaid). Two Olympian 9 s are from Lupinus. 



