AMERICAN HYMENOPTERA. 101 



striated. Abdomen smooth, highly polished. Black, head and thorax 

 opaque; mandibles except the teeth which are reddish, scape in front 

 and tubercles yellow, four anterior trochanters more or less, four 

 anterior legs below the apices of the femora (the tibia; darkened 

 medially) , base of the posterior tibiae and their tarsi reddish or reddish- 

 yellow. Wings clear hyaline, iridescent; venation dark brown. Pec- 

 tus, face and clypeus with rather sparse silvery pubescence. 



Habitat. — Two females, Boulder, Colorado, one on the 

 Campus of the University of Colorado, June 9, 1908 (T. D. A. 

 Cockerell) ; the other June 10, 1908 (S. A. Rohwer) ; one fe- 

 male, Florissant, Colorado, June 14, 1908 (S. A. Rohwer), 

 "on sand." 



I have not seen the male of this species, but from the 

 description of it this seems to be the female. This species is 

 close to mandibularis Cress., but the clypeus is different, the 

 labrum is piceous or black, the apical antennal joint is not 

 longer than the preceeding one, and the markings are yellow. 

 It is also related to czqualis Viereck, but it is larger, the dis- 

 tance between the lateral ocelli is greater than the distance 

 between one of them and the nearest eye margin, the antennas 

 are black, and the third antennal joint is longer than the 

 fourth. 



Ammoplanus eriogoni n. sp. 



Male. — Length 3 mm. Head opaque, appearing punctured but 

 under the compound microscope is finely tessellate. Inner eye margins 

 distinctly converging toward the clypeus. Clypeus in the middle very 

 slightly emarginate; in the basal middle there is a rounded prominence. 

 Frontal suture hardly visible. Ocelli prominent, in a low triangle, 

 the distance between the lateral ones about the same as the distance 

 to the nearest eye margin. Third and fourth antennal joints equal; 

 the apical joint distinctly longer than the preceeding; all the joints 

 rounded out beneath, moniliform. Dorsulum and scutellum opaque, 

 seen under the compound microscope tessellate, with faint indications 

 of furrows on the dorsulum; scutellum not impressed. The suture 

 between the dorsulum and the scutellum under the compound micro- 

 scope foveolate. Mesopleurae opaque, the suture deep. Metanotum 

 rather coarsely tesselate, with small punctures between (the punctures 

 cannot be seen without the compound microscope), in the middle the 

 tessellation is plainer; metapleurag finely tessellated. Venation like 

 .4. columbianus Kohl (Ann. K. K. Nat. Mus. Wien, 1890, p. 61) except 

 that the basal nervure bounding the first discoidal cell is bent in- 



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



