AMERICAN rOLEOPTERA. 1C3 



and the side margin is not visible from above. The elytral striae are 

 composed of approximate punctures, and the inner 

 striae are somewhat impressed. 



S . — The front thighs are armed with a very 

 distinct tooth ; the middle tibiae are produced in- 

 wards at tip into a small cusp, and the terminal spur is slightly curved ; 

 the hind tibiae are obliquely impressed on the inner face, and slightly 

 dilated at tip. terminal spur small, straight. 



9 . — Front thighs not toothed; middle and hind tibiae not dilated 

 at tip. 



I have excluded from the synonymy reference to the descriptions of 

 European specimens which have been considered identical by Erichson, 

 Chevrolat and other authorities, because the hind tibiae are described 

 by Erichson as being dilated in an almost hook-like form, which would 

 indicate a greater resemblance to the r ext species. 



Should they prove on comparison to be different, then it will be 

 necessary for the European species to receive another name. 



In case the name exarafus is considered as involved in too great 

 confusion, in consequence of its use first by Dalman, and second by 

 Serville for two different species, the name americamcs will have 

 priority over aratus which has been adopted by Gemminger and 

 Chevrolat. I have preferred to retain exaratus, for although it was 

 first applied by Dalman to another species, it appears that Fabricius 

 had previously described the latter as Cucuius sukafus. 



2. R. Iiamatus. — Brown-black, shining, head rather obliquely narrowed 

 behind the eyes, which are subtruncate behind, and lateral. Protliorax more 

 than one-half longer than wide, with three very deep entire grooves; elevated 

 spaces sparsely but distinctly punctured. Elytral striae 

 deeper than in the preceding, and more coarsely punc- 

 tured. Length 5.5 — 7.5 mm.; .21 — .30 inch. 



%. — Front thighs armed with a distinct tooth; apical 

 cusp of middle tibise longer, acute; hind tibiae broadly 

 dilated, more deeply grooved on the inner side, with the terminal dilatation 

 transverse, acute at the inner end ; apical spur small. 



$ . — Front thighs not toothed, middle and hind tibise simple. 



California, Mr. Behrens and Dr. Horn. Narrower than the pre- 

 ceding, with the prothorax longer, less suddenly rounded in front, and 

 somewhat less convex. The elevated spaces of the head and prothorax 

 are sparsely punctured, and the elytral striae are much deeper. 



CL.INIDIUJMI Kirby. 

 §. — Prothorax with entire dorsal line, two short deep basal impre.s- 

 sions and double lateral line, elytra costate; middle and hind tibia; 

 with two terminal spurs. 



