1873.] 353 [Horn. 



Basal row of punctures short, arcuate ; mesosternum 

 slightly concave longitudinally sulcate ; meso-meta- 



sternal suture obliterated Floridte. 



Basal row of puuctui-es long, nearly straight ; mesoster- 

 num flat, meso-tmetasternal suture distinct. 

 Form orbicular ; metasternum sparsely and finely 



punctured discus. 



Form oval ; metasternum coarsely punctured fimetarius. 



Prosternum much (usually twice) longer than wide ; meso- 

 sternal stria entire. 

 Elytra with very deep humeral and dorsal strife ; thorax 



very minutely and sparsely puncticulate Sallei. 



Elytra with scarcely a trace of strife ; thorax moderately 

 punctured. 

 Prosternal striaj not more divergent in front than at 



base, elytral punctures much less distinct at base, strigosus. 

 Prosternal stride more divergent in front, elytral punc- 

 tures as deep at base as at middle acaroides. 



A. maritimus, Lee. Ann. Lye. V., p. 170; Proc. Acad., 1853, p. 290. 

 Oblong, feebly convex, brownish-black, shining. Head sparsely pvinc- 

 tulate. Thorax sparsely and finely punctured. Elytra moderately 

 coarsely, but not densely punctured, punctures feebly strigose at apex ; 

 disc with faint oblique dorsal stria extending nearly to the middle of the 

 margin ; marginal stria deeply impressed, entire ; suture slightly chan- 

 nelled at base. Pygidium smooth shining. Prosternum much longer 

 than wide at base, strijB posteriorly parallel, anteriorly very strongly 

 divergent, surface feebly shining, very finely alutaceous. Mesosternal 

 stria entire. Anterior tibite dilated, anterior face slightly concave, outer 

 margin finely spinulose. Length .045 inch ; 1 mm. 



Occurs in California. It is the largest species in our fauna. The 

 measurement above is the entire length, and it is really more than 1 mm. 

 long. 



A. Arizonse, n. sp. 



Bi'oadly oval, convex, brownish-black, shining. Head sparselj'^ i^unc- 

 tulate. Thorax sparsely punctured, punctures at ajjex fine, becoming 

 gradually coarser to base. Elytra rather sparsely and moderately finely 

 punctured, punctures finer at apex ; disc with a short scarcely evident 

 humeral and dorsal stria not attaining the base, marginal stria fine. 

 Pygidium very sparsely punctulate. Prosternum broad, nearly as wide 

 at middle as long, surface sparsely punctured. Mesosternum moderately 

 punctured, marginal stria interrupted, metasternal suture distinct. 

 Metasternum sparsely punctulate. Anterior tibiae scarcely broader than 

 the middle. Length .04 inch ; 1 mm. 



Occurs in Arizona, at Camp Grant, under Cottonwood bark. 



A. exiguus, Erichs. Jahrb., 1834, p. 208 ; Lee. Proc. Acad., 1853, p. 



A. p. S. — VOL. XIII. 2s 



