286 COLEOPTERA OF NORTH AMERICA. 



elytra, a phenomenon of which the first record has been made 

 by Mr. C. V. Riley.* 



Our species fall naturally into the following tribes : — 



Eyes strongly granulated ; 



I. Prothorax pluridentate on the side ; 



3d antennal joint very long. Ergatini. 



3d antennal joint moderate. Mallodontini. 



II. Prothorax parcidentate on the sides ; 

 Metathoracic epimera parallel ; 



Antennae filiform. Derobrachini. 



Antennas imhricate. Prionini. 



Metathoracic epimera narrowed behind. Tragosojiini. 



III. Eyes finely granulated. Solenopterini. 



Tribe I.— ERGATINI. 



One species, Ergates spiculatus Lee. of large size (55-63 mm. 

 long), is not uncommon on the maritime Pacific slope and in New 

 Mexico. The tribe is easily known by the prothorax being much 

 broader in the male than iu the female, and finely punctured ; 

 in the latter sex the sculpture is very coarse, and the small teeth 

 of the lateral margin longer and more acute. The head is small, 

 the eyes reniform and coarsely granulated ; antenna? 11-jointed, 

 slender, two-thirds the length of the body in the £ , about half 

 the length of the body in the 9 , rough with elevated punctures, 

 with the 3d joint as long as the three following united ; pori- 

 ferous spaces on the 3d joint small inconspicuous, on the under 

 surface near the distal end, gradually becoming larger, until the 

 outer joints become entirely poriferous, and irregularly reticulated 

 with fine elevated lines forming elongate cells, which are much 

 less distinct, and in fact hardly to be seen in the male. 



The generic characters are not sufficiently distinct from the 

 European species E. faber to warrant the retention of the genus 

 Trichocnemis proposed in my earliest description of this insect. 



Tribe II.— IWAI^ODONTIIVI. 



This tribe contains also species of very large size (one from 

 Florida in my collection is 61 mm. long), with the sides of the 

 prothorax armed with numerous small teeth. The head is com- 



* Canadian Entomologist, iv. 139. 



