AMERICAN COLEOPTERA. 287 



West Indies to South America, as far as Chili and Buenos Ayres. 

 1 ypical spcciujeus have been sent uie through tlie kindness of Dr. 

 Candeze, from the l'an)pas of the latter country where they appear to 

 be as abundant as in our own regions. 



"• It is our largest t^pecies and may readily be known by its shining 

 black color, deeply striate and erenately punctured elytra with inter- 

 vals at least moderately, sometimes very, convex and smooth. The 

 thorax is doubly punctured, tl^at is, there are fine punctures, moder- 

 ately, densely placed and much coar.ser and deeper punctures irregu- 

 larly di.sposed but much more abundant at the sides and base than on 

 the disc and in front. The thorax varies somewhat in shape being 

 apparently broader in front in the specimens known as " stercorator" 

 in our cabinets and moderately ruunded and apparently narrowed in 

 front in the types from Candeze and in ror/nafus, Lee; sfi-if/afus, is in 

 all respects intermediate, in fact the variation here is no greater, if as 

 great as in Ajthoduix graimrms, which appears to exhibit slight varia- 

 tions in each locality when varied conditions of habitat are found. 

 Length .1<5 — .24 inch; 4 — mm. 



At. lobatus, n. sp. — Piceoiis black or brownish, shining. Head moderately 

 convex sparsely punctured and transversely strigose in front. Thorax moder- 

 ately convex, one third broader than long, sides rounded, base broadly lobed 

 at middle; surface with sparsely placed fine punctures and very coarse, deep 

 punctures at the sides and base not densely placed. Elytra oblong, broader 

 behind the middle, very obtuse at apex; surface deeply striate, strise punc- 

 tured, intervals very convex, s^mooth. Body beneath nearly smooth, legs cas- 

 taneous. Length .22 inch; 5.5 mm. 



This species may readily be known from stervorator, by its brown 

 color. A.S compared with the latter species the thorax is shorter the 

 sides more rounded and the base more distinctly lobed. The coarse 

 punctures of the thorax are much fewer and never densely placed. 

 The punctures of the striae are smaller never so closely placed and 

 have a tendency to become evanescent. The elytra in stercorator^ are 

 parallel in the present species rounded on the sides broader behind the 

 middle and more convex both transversely and longitudinally. 



Occurs rather abundantly in the Peninsula of Lower California. 



At. socialis, n. sp. (Harold k Chevr. mss.) — Oblong, subjiarallel, shining, fer- 

 ruginous with occiput, disc of thorax, suture and apex of elytra darker. Head 

 moderately convex, sparsely [)unctured. Thorax one fourth broader than long, 

 sides feebly rounded; surface sparsely punctured, punctures coarser at the 

 sides and base. Elytra twice as long as broad, parallel, striate, stria; feebly 

 punctured, intervals moderately convex and smooth. Body beneath smootii 

 shining, similar in color to the ujijier surface. Length .18 — .20 inch ; 4.5 — 5 

 mm. 



