ROLAND HAY WARD. 51 



35. A. iiiMiiItiris Horn. 



A^ery clo.se to the preceding, from wliich it difier.s by its slightly 

 more convex and more robust form, and by the ab.sence of punc- 

 tures at the sides of the base of the thorax. I have never seen 

 any specimens with bluish surface lustre, all having a distinct 

 seneous tinge. The femoral setce are as in insignis, and the males 

 have a large, deep puncture at the middle of the prosternum, as in 

 that species. Its length ranges, in some thirty examples studied, 

 from .37-.45 inch; 9.25-11.25 mm. 



It occurs on the islands along the coast of the southern |)art of 

 California. Most of the specimens seen are from Santa Barbara 

 Island, San Nicolas Island and Santa Rosa Island. 



36. A. impuiicticollis Say. — Foitn oval, convex. Color aeiieotis or nigro- 

 seneous, often tinged with green, shining, the surface alutaceous in the females. 

 Head slightly narrower than the thorax at apex ; antennse shorter than the head 

 and thorax, not carinate, the three basal joints rufous, the outer ones darker; 

 palpi rufopiceous. Prothorax subquadrale, at base as wide as the elytra, nar- 

 rowed from slightly behind the middle to apex; surface impuncitate; apex 

 deejily emarginate, the anterior angles prominent hut rounded ; transverse and 

 basal impressions obsolete or nearly so, the latter rarely feebly marked, especially 

 the inner fovea ; median line fine, abbreviated before and behind ; sides with the 

 margin nsirrowly reflexed, slightly rounded in front, subparallel behind : base 

 very feebly bisinuous; hind angles rectangular, rounded at tip, not carinate, the 

 posterior lateral setigerous puncture nearer the basal than the side margin. 

 Elytra striate; strife entire, iinpunctate, the scuteliar strise terminating in an 

 oceiiate puncture, the eighth stria with the row of ocellate punctures narrowly 

 interrupted at middle; intervals flat or nearly so. Body beneath black, impunc- 

 tate; prosternum rounded at tip. Femora piceous, tibiae and tarsi rufous or 

 rufopiceous; all the femora with two setigerous punctures along the inner mar- 

 gin; middle and hind tarsi with the basal joint grooved on the outer side. 

 Length .28-.40 inch ; 7-10 mm. 



A stuily of a large series of specimens show.s a comparativelv 

 slight range of variation, this being principally in brilliancy of 

 color, size and in the distinctness of the l)asal impressions. U.suallv 

 the latter are obsolete or nearly so, while in a comparatively few 

 the inner fovea, although very shallow, is moderately distinct and 

 linear, the outer, at most, existing as a faint and verv poorlv defined 

 depression. 



It seems to make the nearest approach to the subgenus Trurna. 



From most of our other species it is at once recognizable bv the 

 presence of an ocellate puncture at the base of the scuteliar stria, a 

 character occurring in nearly all our species of Tr'nvnn, but observ- 



TR.\NS. AM. ENT. SOC. XXXIV. MARCH. 190S. 



