AMERICAN COLEOPTERA. 339 



s\irface more coarsely and densely punctured. Length 1.25 — 1.08 "J, and 1.12 9 

 inch ; 32—27 luin % and 28 mm 9 . 



This species in its elytral sculpture is exactly iaternicdiate between 

 our other two species eremicola and scahra. The surface of the thorax 

 is sculptured after the style of the latter species but in a more exajr- 

 ticrated degree. The anterior margin of the front is more reflexed 

 than either. It may distinguished at once from either species by hav- 

 ing the presternum in front of the coxae less convex and s(ro7u/I)/, 

 transversely icrinklcd, as well as broader. The color of the surface 

 varies somewhat. There is at times only the ground color (casta- 

 neous) visible, while others have a distinct greenish lustre. Its form 



is bro:ider and more robust than eremicola. 



t 

 CEEMASTOCHILUS, Knoeh. 



During an examination of my specimens of the above genus two 

 were found that could not be referred to any described species and the 

 present opportunity is made use of to present to students of our fauna 

 the results of my own observations. As will be seen by the annexed 

 table the species divide themselves very naturally into three groups 

 according to the form of the mentum. The more nearly we approach 

 tlie Pacific the more acute dees the cupule of the mentum become at 

 its hinder angle and as a general rule less deep in its concavity. On 

 the eastern slope the mentum is broader, the cupule deeper and at the 

 posterior portion notched to the bottom. Two California species have 

 decidedly fossorial legs, the tibiae being broader and shorter and the 

 tarsi very short and compressed. These two {Schaumii and ani/nlaris) 

 I found very frequently in ants' nests and in one instance apparently 

 eating the pupae. Several times I have seen large black ants dragging 

 specimens of /S'c/iajAmtY along the surface of the ground toward their 

 nests and on examination have frequently succeeded in obtaining from 

 nests specimens that had previously been dragged there. Why these 

 insects are found with ants is a question to which I am not prepared 

 to give a definite answer, unless as I suspect the fossae at the anterior 

 angles and the finely punctured and apparently perforated patches un- 

 der the hind angles are glandular and yield some secretion grateful to 

 the ants. 



The following table gives the result of a short study. 



Mentum plate acutely angulate behind. 



Anterior tarsi with last two joints rather suddenly thicker. 

 Teeth of anterior tibice distinct; hind angles of thorax moderately ' 



prominent planatus, Lee. 



