MORGAN HEBARD 361 



zones of the High Sierras, being found in a more rigorous environ- 

 ment than other species of the genus. 



The cereal abbreviation in albida is exceeded only in B. satur 

 Scudder, a very distinct species. 



Type. — cf; Lone Pine Lake, Whitney Pass Trail, Sierra Nev- 

 ada Mountains, Inyo County, California. Elevation, 10,000 to 

 10,100 feet. September 6, 1919. (Rehn and Hebard.) [Heb- 

 ard Collection, Type no.' 565.] 



Size small for the genus, form rather heavy. Surface subglabrous, well 

 supplied with elongate though exceedingly fine hairs. Head broad and 

 full; vertex gently tumid, fastigium very shallowly concave between eyes, 

 the lateral margins not at all carinate; frontal costa deplanate, showing 

 very slight depression at the median ocellus, there as wide as the interocular 

 space, immediately below that portion suddenly narrowed by a fine but 

 distinct and sharply curved sulcus on each side, completely obliterated be- 

 low, where the face, above the clypeus, is evenly convex. Eye only slightly 

 longer than wide, one and one-third times as long as the infra-ocular sulcus. 

 Pronotum short, with disk rounding into the lateral lobes without carina, 

 lateral lobes with prozonal section moderately inflated in dorsal portion, 

 this cut vertically by the median transverse sulcus, which on the disk is weakly 

 indicated mesad and obsolete meso-laterad, first transverse sulcus distinct 

 only on disk, principal transverse sulcus subobsolete on disk; medio-longi- 

 tudinal carina of disk weakly indicated near cephalic margin and on meta- 

 zona, elsewhere obsolete; caudal margin of disk almost transverse, very 

 broadly obtuse-angulate emarginate at the intersection of the nearly trans- 

 verse though very broadly convex halves. Tegmina and wings absent. 

 Abdomen with a fine but distinct medio-longitudinal carina. Furcula rep- 

 resented by two slightly produced convexities of the tergite at its median 

 emargination. Supra-anal plate elongate shield-shaped, raised in a weak 

 shoulder at lateral margins on each side at end of proximal two-thirds, lateral 

 portions broadly and deeply concave, median portion raised, in proximal 

 half with surface concave between heavy convergent lateral carinae, in distal 

 half weakly convex except for a small sub-apical impression. Cerci small, 

 not twice as long as proximal width, lateral margins very weakly concave, 

 converging to near apex, there the dorsal margin curves obliquely downward 

 to the sharply rounded apex. Subgenital plate roughly conical, tapering 

 to the produced and bluntly rounded apex, with surface ventro -mesad show- 

 ing a weak concavity, lateral margins almost straight to apex. Cephalic 

 and median femora slightly inflated, very weakly bowed. 



Allotype. — 9 ; same data as type. [Hebard Collection.] 

 Much larger and more robust than male. Head with interocular space 

 wider and showing scarcely any concavity, frontal costa at median ocellus 

 four-fifths as wide as the interocular space. Pronotum similar to that of 



TRANS. AM. ENT. SOC, XL VI. 



