THE CANADIAN ENTOMOLOGIST. 149 



THE COLEOPTERA OF CANADA. 



BY H. F. WICK HAM, IOWA CITY, IOWA. 



XXIX. The CEdemerid.^<: and Cephaluid/e of Ontario and Quebec. 



The family (Edemeridae is of small extent, only five species, represent- 

 ing four genera, being recorded from the region under discussion. None 

 of our species are very small and two of them at least often reach a size 

 sufificient to render them readily noticeable. With the exception of 

 Nacerdes melanura, which frequents houses, wharves, lumber piles and 

 shipping, they are to be found on bushes and trees or else under boards 

 in wooded districts. 



Technically they may be defined as beetles having the hind tarsi 

 four-jointed, the remainder five-jointed ; the anterior coxal cavities open 

 behind ; the head not strongly and suddenly constricted at base ; and 

 the middle coxae very prominent. The claws are either simple, dilated 

 at base or with a basal tooth. 



In appearance the genera differ considerably ; however, those in our 

 fauna belong to the three types of habitus of which figures are given, 

 Nacerdes resembling Asclera in general form. It is hoped, therefore, 

 that the collector may have no difficulty in identifying his Canadian 

 captures. The generic table following is constructed on the lines laid 

 down in the Classification and in Dr. Horn's recently published memoir : 



A. Eyes deeply emarginate, embracing the base of the antennge, which 

 are nearly as long as the body. Appearance much like a slender 

 Elaphidion Calopus. 



AA. Eyes entire or nearly so. 



b. Form robust, colour black with faint violet tinge. Tarsi with 

 several joints spongy-pubescent beneath Ditylus. 



bb. Form slender, colour in part reddish or yellow. 



c. Anterior tibige with one spur. Colour above yellowish, 

 elytra tipped with black. Antenna3 of male twelve- 

 jointed Nacerdes. 



cc. Anterior tibiae with two spurs, antennae eleven-jointed 

 in both sexes. Colour blackish, prothorax wholly or 

 in part reddish Asclera. 



Of course, it must be understood that the colour-characters given 

 above are intended to apply only to the Canadian species. 



