268 FOSSIL COLEOPTERA 



Isomira aurora sp. nov. (Plate V, fig. 6.) 



Form moderately elongate, subparallel for most of the length. Head of 

 normal size, eyes not well defined but remote, front minutely punctulate. 

 Antennae much longer than the head and prothorax united, slender, not 

 serrate, the joints succeeding the second subequal in length. Prothorax 

 much narrowed anteriorly, sides arcuate, width equal to about one and 

 three-fourths times the length, surface minutely punctured and finely, 

 moderately closely hairy. Elytral sculpture and vestiture similar but a 

 little more pronounced. Legs slender, poorly preserved. Length, 10 

 mm. ; to elytral apices, only a very little less. 



Described from one specimen, with counterpart, found by myself 

 on the Wilson Ranch, near Florissant, Colorado. The type is in 

 my collection. 



The measurement is taken from the lower impression, which is 

 not broken at the posterior extremity. The insect is pretty 

 large for Isomira, but I think it belongs in that immediate vi- 

 cinity and the Cistelide genera, at best, are often excessively poorly 

 differentiated. 

 Mordellistena scudderiana sp. nov. (Plate V, fig. 7.) 



Of the usual cuneiform outline, not very slender. Color apparently 

 brownish or testaceous. Head rather small, antennae wanting. Prothorax 

 moderately strongly arched dorsally, surface minutely but clearly punc- 

 tulate and pubescent. Elytra more or less overlapping, too much dam- 

 aged to allow their shape to be made out clearly, but the remaining por- 

 tion is well preserved, showing a fine punctuation, stronger than that of the 

 prothorax, and a pubescent vestiture. Anal style short and strong, pointed 

 at apex. Ventral sclerites of thorax and abdomen smoother than the 

 elytra. Legs lacking except one belonging to the hind pair which has a 

 moderately thickened femur. Length, over all, 4.90 mm. 



Described from one specimen, with counterpart, preserved in 

 profile. It was collected by myself on the Wilson Ranch, near 

 Florissant, Colorado. The type is in my collection. 



Closely related, as far as visible characters go, to M. protogaea, 

 but of considerably greater size. 



Mordellistena nearctica sp. nov. (Plate V, fig. 8.) 



Form slender. Head and prothorax fused together by crushing so that 

 the form of each is obscured. Eye large. Antennae wanting. Elytron 

 narrow, the apex damaged so that its exact shape is not determinable. 

 Abdomen extending well beyond the elytral apices, its tip pointed, the anal 

 style rather long, not much tapered, apex blunt. Hind leg with stout and 

 short femur and tibia, tarsus not defined. Length, to elytral apex, 3.25 

 mm.; to tip of anal style, 4.15 mm. 



