AMERICAN COLEOPTEHA. 95 



few minute punctures, almost entirely smooth beneath. Length .18 — .20 inch; 

 4.5 — 5 mm. 



Male. — Last ventral deeply divided, lobes not divergent nor curved. Sixth 

 ventral subtruncate feeble emargination at middle, pectinate along the margin 

 with very short spinules forming a continuous series, a few spiuiform tubercles 

 near the posterior margin and several on the fifth ventral. Last dorsal four- 

 dentate but with the teeth more acute than in maculicollis, (fig. 8, a). 



Female. — Last dorsal with lateral lobes rather slender, middle lobe slender, 

 as long as the lateral, cleft half to base, (fig. 8, b, too deeply cleft). 



The facies of" this species is somewhat tliat of Tachyporus, being 

 more robiu>*t in body and more attenuated posteriorly than anj' species 

 of Tachinus in our fauna, this together with the longer antenntx) gives 

 it a facies altogether peculiar. It is however a true member of the 

 present genus. The color is variable, mature specimens are entirely 

 piceous. others less mature have the thorax and elytra more or less 

 bordered with testaceous and their legs paler. 



Occurs in California, Vancouver and North Red River. 



T. agilis, n. sp. — Form and sculpture of tachyporoides, but somewhat darker 

 in color, legs always piceous. Length .18 — .20 inch; 4.5 — 5 mm. 



Male. — Last ventral deeply, acutely einarginate, forming broad triangular 

 plates, sixth ventral semicircularly emarginate at middle, spinules short, 

 arranged at each extremity of the emargination, face of segment broadly 

 longitudinally impressed, a few granules near the emargination. Last dorsal 

 as in tackyporoide.s, (fig. 9, a). 



Female. — Last ventral with six processes, the two middle rather short and 

 broad. Last dorsal with middle lobe as long as the outer cleft one-third to 

 base, (fig. U, b). 



This species resembles taclujporuides so closely that the sexual differ- 

 ences of the males alone separate them. The females do not differ 

 except slightly in color. From uugiistafus besides the sexual differ- 

 ences, the form of agiliii is much more robust and convex. 



Occurs in California, Crystal Springs. 



T. Riigii!^tatlii$, n. sp. — Form slender, piceous black, shining. Antennae 

 slender, entirely piceous. Thorax shining, with a few very minute punctures 

 sparsely placed. Elytra slightly longer than wide, shining, obsoletely j)unc- 

 tured. Abdomen sparsely and finely punctured, scarcely at all alutaceous. 

 Length .20 inch; 5 mm. 



Male. — Last ventral deeply divided, forming two triangular processes not 

 curved and rather short. Sixth ventral feebly concave, broadly emarginate 

 at middle, on each side pectinate with rather long spinules, hind margin at 

 middle with narrow spongy space, face of segment without it. Last dorsal as 

 in maculicollis, (fig. 10, a). 



Female. — Last ventral as in inafulicollis. Last dorsal with rather broad lateral 

 lobes, middle lobe about three-fourths as long and deeply divided forming two 

 slender processes, (fig. 10, b). 



Four specimens, two % , one 9 Colorado, one % California. 



