AMERICAN HYMENOPTERA. 99 



New Hymenoptera from Western United States.* 



BY S. A. ROHWER, BOULDER, COLO. 



Passaloecus fasciatus n. sp. 



Female. — Length about 10 mm.; length of anterior wing about 6 

 mm. Head rather transverse, about the same shape as Passaloecus 

 mandibularis Cresson. Antennae twelve- jointed, moderately stout; 

 fourth joint longer than third. Prothorax rather than usual, sharply- 

 truncate anteriorly; propleurae longitudinally striate above. The dif- 

 ference in height between the dorsulum and prothorax is not as great 

 as in P. mandibularis; dorsulum apparently impunctate; meso- 

 pleuree apparently finely transversely striated. Metanotum renticu- 

 lated (this could not be seen very clearly with a hand lens, but the 

 compound microscope showed it plainly). The metapleuras and pos- 

 terior face strongly, transversely, striate-rugose. Legs perhaps a 

 little stouter than in the modern members of the genus; posterior 

 tibiae without spines. Venation very much the same as in P. mandi- 

 bularis; stigma large, rounded on the lower margin; the shape and 

 position of the basal nervure is just the same as in P. mandibularis; 

 radial cell of the usual shape, wider at the base, in front of stigma 

 tapering to an acute apex; second tran. cu. (the first is wanting) 

 sharply bent in the middle, and with a spurious nervure running in 

 the direction of the third tran. cu. Abdomen long and flattened, 

 much the same shape as the abdomen of Crabo (Xestocrabo) trifasciatus 

 Say; the abdomen of Passaloecus as a rule is shorter and more cylin- 

 drical. The head and thorax black; the abdomen black or dark 

 brown, with a narrow band on the second and a broader one on seg- 

 ments 3-5 pale, probably yellow. Wings hyaline, venation brown. 



The following measurements are in micromillemeters : — 



Length of the third antennal joint 204. 



Length of the fourth antennal joint 306. 



Length of the 2 tran. cu. above the spurious nervure 204. 



Length of the basal nervure between the cu. and costa 340. 



First recur, basal of the 2 tran. cu 850. 



Second recur, basal of the 3 tran. cu 221. 



Tran. med. to besal 51. 



Length of stigma 765. 



Width of stigma at origin of the cubitus 170. 



Length of the third tran. cu 595. 



Habitat. — -Station 13B of the Tertiary Shales of Florissant, 

 Colorado (S. A. Rohwer), 1908. Type in the University of 

 Colorado. 



* I wish to acknowledge my indebtedness to Prof. T. D. A. Cockerell 

 for going over my manuscript. 



TRANS. AM. ENT. SOC, XXXV. MARCH, 1909. 



