262 COLEOPTERA OF NORTH AMERICA. 



Sub-Tribe 1. — Cetosiiini (genumi). 



The elytra in the genera here placed are always sinuate on the 

 side, and the mesosternum is almost always prominent; the epi- 

 mera of the mesothorax ascend between the prothorax and elytra, 

 and are visible from above. The foreign genei-a exhibit an intri- 

 cate network of affinities, which all the labor of Burmeister and 

 Lacordaire has failed to represent in a synoptic form; our fauna 

 is so limited, however, that our groups may be thus defined : — 



Mandibles feeble, in great part membranous ; last siiiracle midway between 

 the anterior and posterior margin of the segment ; 



Prothorax lobed at the base, covering the scutellum. Gymnetbs. 



Scutellum not covered by the thorax. CExoNii^. 



Mandibles Avith the outer part thickened ; last spiracle near the posterior 



margin of the segment, the suture nearly effaced. Ckemastochili. 



Group I. — Gymnetes. 



But two genera of this group occur in our fauna : Allorhina 

 having the clypeus armed with a short horn; Gymnetis with the 

 clypeus flat. 



Allorhina nitida extends over the Atlantic slope, and is a 

 well-known green, velvety insect, nearly an inch long, somewhat 

 pointed in front, with the sides of the thorax and elytra usually 

 brownish-yellow. Other species will probably be found in our 

 southwestern territories. 



Gymnetis Sallei is found in Louisiana, Texas, and Mexico. 

 It is a beautiful velvety, olive-colored insect, of the same form 

 as Allorhina, three-fourths of an inch long, variegated with pale 

 yellow marks, which unite on the margin of the thorax and elytra. 



No species of this group has yet been found on the Pacific 

 slope. 



Group II. — Cetoniae. 



Our species, although arranged by Burmeister in three genera 

 — Euphoria, Erirhipis, and Stephanucha — have been united by 

 Lacordaire with other foreign forms, and for the combined genus 

 lie retains the name Euryomia. The views of European authors 

 do not seem to be in accord in the division of the old genus 

 Cetonia, and as the group is not sufficiently represented in our 

 fauna to permit a discussion of the subject, the name Euphoria 

 has been retained as least objectionable. 



No species has yet been found on the Pacific slope. 



