Goleopterological Notices, VII. 591 



The last ventral of the male is not distinctly tumid in the 

 middle near the base and has a rather large oval and decidedl3^ 

 ■deep concavit}^ rather well defined, slightly wider than long and 

 extending from near the base to the apical margin, which is 

 broadly lobed ; last dorsal parabolic, finel}^ and remotelj' punctu- 

 late, with a small and moderately deep rounded apical sinus 

 limited hy broadly rounded angles. 



This species differs from both ruhicunda and kansana in the 

 much deeper concavity of the last ventral, and, from gracilis, 

 ■which also possesses a deeply concave last ventral, it differs in its 

 nearly parallel and not widely divergent abdominal carinse, 

 smaller and less transverse prothorax and smaller sinus of the 

 last dorsal, this segment also being much less punctate. 



The four species ruhicunda, kansana, gracilis and ursina form 

 -a. natural group, distinguished by the long bristling pubescence. 

 The species are closel}^ allied among themselves in general ap- 

 pearance, but appear to be definable b}' the characters given in 

 the table. The material before me is not sufficiently extensive 

 to disclose possible variations in the extent and direction of the 

 abdominal carinse, which exist to a visible degree without doubt. 



R. Iiisolita. — Moderately ventricose, the hind body oblong-elougate, 

 strongly convex, highly polished, subimpunctate, piceous-black, the elytra 

 Tuf ous, the abdomen black ; legs and antennse pale ; pubescence very short, stiff, 

 recurved, only moderately dense, the elytra with a few remotely placed, short 

 and erect tactile hairs visible under high power only. Head quite distinctly 

 narrower than the prothorax. normally foveate, scarcely punctulate, the eyes 

 prominent and well developed, at much less than their own length from the 

 "base. Antennse slender, distinctly longer than the head and prothorax, the 

 club gradually formed and not very stout ; second joint much narrower than the 

 first and not quite }4, longer than Avide ; three to eight still much narrower, 

 'equal in width ; third f^j, fourth and sixth barely J^, fifth 1, and seventh 

 %, longer than wide ; eighth as long as wide; ninth obtrapezoidal, rather 

 longer than wide; tenth nearly as long as wide, the eleventh obliquely pointed 

 and as long as the three preceding combined. Prothorax scarcely ij^ wider than 

 long, widest at about the middle, the sides moderately strongly rounded, con- 

 vergent and sinuate to the base, the apex barely ^ as wide as thB base; disk 

 strongly convex, finely, sparsely punctulate, the median fovea small but deep 

 and perforate. Elytra but slightly shorter than wide, twice as wide as the 

 prothorax, and ^ longer, the sides moderately divergent and broadly arcuate; 

 humeral swelling pronounced; striae fine but strong. Abdomen as wide as 

 the elytra, shorter when viewed vertically, the first segment }4. ^s long and 

 nearly three times as wide as long, the carinse fine, straight, about % as long 

 as the segment, divergent and separated at base by slightly, though distinctly. 



