THE CANADIAN ENTOMOLOGIST. 



23 



Fig. 



DoRCUS, MacL. 



Somewhat like Lucanus, but the species are rather smaller, and the 

 teeth on the front tibiae are less pronounced, becoming mere serrations 

 on the proximal portion. D. parailelus. Say, is dark brown, nearly black, 

 the head and thorax shining, with fine sparse punctures. Elytra distinctly 

 striate, the stri;« and interstitial spaces both evidently and rather closely 

 punctured. In the males the head is nearly as broad as 

 the thorax, and the mandibles have an enormous median 

 tooth, which points obliquely " inward and upward. 

 Length, .60-1.04 i^i- The form called brevis, Say (fig. 

 13, after Packard), is smoother, and the head and thorax 

 are much more developed. This variety is rare, and I 

 have never seen it. 



Platycerus, Geoff. 

 These are much smaller insects than those belonging to the foregoing 

 genera. The eyes are nearly entire instead of being notched in front by 

 the encroachment of the sharp side margin of the head, and the anterior 

 tibife are armed externall} with numerous fine sawlike teeth. The 

 mandibles of the males have an upward inclination and are larger than 

 those of the females. 



Sides of prothorax rounded, hind angles rather obtuse or rounded. 

 Brownish, greenish or bluish, shining, elytra! strige less deep. 



.40-48 in quercus, Web. 



Sides of prothorax quite distinctly angulate near the middle, hind 

 angles rectangular, distinct. Blackish, often with slight metallic 

 reflections. Elytral striae deeper, surface less shining. .44-.53 

 in , depressus, Lee. 



In the Pacific provinces other species are found. P. ofegonensis, 

 Westw., is known from Vancouver Island. It is of a bluish colour, and 

 looks something like depressus as far as form is concerned, but may be at 

 once distinguished from that species by having the sides of the thorax 

 straighter in the male and the hind angles obtuse or indistinct. It is of 

 the same size as depressus. P. Keeni, Casey, from the Queen Charlotte 

 Islands, was described in the Can. Ent., Vol. XXVIL, p. 153, so it is 

 not worth while to repeat the characters here. It is .50 inch long, stouter 

 than oregonensis, the elytra subcostulate and the legs very thick. The 

 type was of a blackish-castaneous colour, 



