AMERICAN COMPONENTS OF THE TENTYRIIN^E 449 



The original specimens were taken by Mr. Gabb, and the 

 only one in the collections reported upon by Dr. Horn (Proc. 

 Cal. Acad. Sci., IV, 1894) from San Jose del Cabo, is said to 

 be somewhat aberrant, having the prothorax less narrowed 

 behind and the stri^ better marked, with coarser punctures. 

 The prothorax therefore seems to be narrowed toward base in 

 ■puncticollisy although this is not directly stated by the describer. 



Tribe Edrotini. 



This tribe, through the Erodiini, connects the preceding tribes 

 with the remarkably divergent Adesmiini and Craniotini. The 

 prominent unemarginate eyes and very acute and anteriorly 

 prolonged thoracic angles, constituting such marked features, 

 were presaged in Micronies or Trie/notes and Oxygonodera of 

 the Triorophini but, because of its peculiar habitus and structure, 

 there can nevertheless be no question of its profound isolation. 

 Epiphysa, although placed tribally with Edrotes by Lacordaire, 

 seems to differ so greatly in the structure and degree of separa- 

 tion of the hind coxge and form and vestiture of the tarsi, as 

 well as in general facies and geographic distribution, as to 

 require a tribal group by itself, and indeed that author himself 

 placed the two genera in different subtribal groups of his " Epi- 

 physides " or Epiphysini. The tribe Edrotini is confined to the 

 Sonoran regions of North America and, so far as known, is 

 represented only by the two following genera : — 



Body rounded, convex, with sparse conspicuous erect hairs, the head 

 large, the epistomal lobe quadrate, with its sides parallel and sin- 

 uate and apex broadly angulate nearly as in Triot'ophus^ clasped 

 by a basally somewhat bulbose, thin dorsal ridge of the mandi- 

 bles, the latter stout, convex, with the internal dorsal ridge termi- 

 nating on each in a porrect acute tooth clasping and retracting 

 the labrum, the apex obtusely and unequally bifid and impressed 

 for some distance behind the shallow incisure; mentum trans- 

 versely hexagonal, the apex trisinuate, the median sinus smallest 

 and most angular; eyes small, very convex and prominent, mod- 

 erately coarsely faceted and unemarginate, the surface without a 

 fine supra-orbital carina but occasionally obtusely ridged at some 

 distance above the eyes ; antennae long and slender, the four or 

 five outer joints larger, the eleventh pyriform and as long but 

 scarcely so wide as the tenth ; prothorax with very prominent 

 and acute apical angles, strongly transverse, not acutel}' margined 



