banks: new fossorial hymenoptera. 115 



of mandibles, spot back of eyes, and the scape, yellow; flagelluni 

 mostly rufous, but base black; two spots on pronotum, tegulae, 

 tubercles, two spots on scutelhmi, postscutellum, two spots each side 

 on metanotum, and apical band on abdominal segments, yellow; 

 basal two thirds of femora and apex of hind tibiae black, rest of the 

 legs yellow. Enclosure strongly transversely striate, not punctured 

 as in C. finitima; the pygidium is slender and about equally narrowed 

 at each end as in C. finitima. The narrowing or indentation of the 

 abdominal bands is present in both specimens, but is uncommon in 

 C. finitima. Length, 6.5 mm. 



Cerceris hesperina, sp. nov. 



Typc.— M. C. Z. 10,031. Washington: Yakima, July, 1882; 

 Ainsworth, July, 1882. Samuel Henshaw. Four specimens. 



9 Similar to C. finitima; small, coarsely punctured, black species, 

 •wath clypeus, spot on lateral lobes, sides of face, bases of mandibles, 

 and scape beneath, yellow. Flagellum rufous beneath. Two spots 

 on pronotum, tegulae, tubercles, two spots on scutellum, postscutel- 

 lum, median spot on first segment, broad band on second segment, 

 and narrow bands on other segments, that on the third sometimes 

 broken into three transverse marks, yellow; most of femora, apical 

 half of hind tibia, and mid and hind tarsi blackish. Face broad, rather 

 densely clothed with short white hair below; enclosure smooth in 

 middle, finely striate on sides; the pygidium broader than in C. 

 finitima, but narrowed at each end. 



The male is similar; the lateral lobes unmarked; the spot on basal 

 segment may be lacking, the enclosure polished, but slightly punctate 

 on the sides, the pygidium rather broader than in the male C. finitima, 

 and barely if at all narrowed at base. Length, 6 to 8 mm. 



