NORTH AMERICAN COLEOPTERA. 173 



aeneous lustre, much coarser elytral sculpture, and in tlie 

 sexual characters; both the anterior and middle tarsi of the 

 male in ramosa are strongly dilated. All the many speci- 

 mens which I have seen are aeneous above, and this appears 

 to be a very persistent character. The form is mentioned 

 by Mannerheim (Bull. Mosc. 1843, No. 2, p. 252) as Sil2^ha 

 cervaria, Var. b. It is also mentioned by Dr. Horn (Tr. 

 Am. Ent. Soc. YIII, p. 241) as one of the variations of S. 

 ramosa Say. 



S. cervaria Mann. — This is apparently a valid species, 

 being represented in my cabinet by two specimens of un- 

 mistakably more broadly oval outline than ramosa; the 

 dorsal surface also exhibits very decided differences in 

 sculpture. 



BATRISUS Aube. 



Although this large and important genus is in a state of 

 comparative confusion, it is believed that the description 

 of the following forms is warrantable, since no species have 

 yet been described from California, and the possibility of 

 increasing our synonymy is, therefore, very slight. It is 

 true that B. alhion{cusA\ihe h.?i& been ascribed to California, 

 but as the locality is not mentioned by Aube in either of his 

 descriptions, this would appear to be more or less doubtful; 

 at any rate it is easily distinguishable from any of the spe- 

 cies here described. 



The following species all belong to the group having tri- 

 sulcate and bituberculate pronotum, although in one or two 

 forms the median channel becomes almost or quite obsolete; 

 they also agree throughout in haviug a terminal process at 

 the apex of the posterior tibiae, and in the similarit}^ of the 

 sexual characters. The latter are well marked, and are as 

 follows: — 



Male. — Abdomen more or less deeply impressed near the apex; terminal 

 process of posterior tibise short and nearly straight; intermediate trochanters 

 13— Bull. Cal. Acad. Sci. II. 6. Issued November 27, 1886. 



