REVISION OF TENEHRIONID SUBFAMILY CONIONTIN^ I47 



pleurae are more narrowed toward apex than in Coniontis and 

 are concave toward base ; they are very finely, feebly and 

 sparsely punctate. 



Coelotaxis Horn. 

 This genus is a development from the archetypes of Coniontis^ 

 by reason of isolation on the solitary Island of Guadalupe, 

 probably during the time elapsing between some epoch in the 

 late Tertiary and the present time ; it is in fact simply Coniontis 

 with feebly ciliate sides of the body, shallow and submuricate 

 punctuation, subexplanate sides of the pronotum, rather more 

 developed and more obliquely truncate basal joint of the an- 

 terior tarsi, somewhat less elongate basal joint of the hind tarsi, 

 less impressed mesosternum and extremely minute scutellum, 

 the last being the most important and striking differential feature. 

 It is scarcely more closely allied to Cozliis than is Coniontis 

 itself, any apparent resemblances, such as the ciliate sides of 

 the body, being merely superficial or directly due to some 

 similarity in habits. It is rather remarkable, when we con- 

 sider the very circumscribed habitat of the genus, that several 

 species, more or less closely allied it is true, should have been 

 gradually evolved ; these as represented in my cabinet by large 

 series, in all except two of the species, may be defined as 

 follows : — 



Epistomal sinus larger, in the neighborhood of a third as wide as the 

 maximum width of the head ; anterior angles of the prothorax 

 somewhat deflexed, the lateral bead more or less fine 2 



Epistomal sinus very small, barely a fifth as wide as the head and very 

 shallow, the lobes broadly rounded ; anterior thoracic angles not 

 deflexed, the lateral bead unusually thick 6 



2 — Elytra shining, rather sparsely and much less conspicuously punc- 

 tured, the pubescence shorter and barely visible. Form broadly 

 oblong-oval, strongly convex, dark blackish-brown, the under 

 surface, legs and antennae paler ; head coarsely, densely punctate, 

 broadly rounded, the sinus moderately shallow, subangular, the 

 sides broadly rounded, very much more prominent than the eyes or 

 the posterior canthus ; antennae long and very slender, the third joint 

 much longer than the fourth; prothorax slightly more than twice 

 as wide as its median length, the sides broadly, subevenly rounded 

 and converging from base to apex, a little more strongly so toward 

 the apex, which is three-fifths as wide as the base, deeply and 

 evenly sinuate, the angles but little deflexed and merely somewhat 



