OF THE TABANIDiE OF THE UNITED STATES. 471 



outline of the whole body (in the female), owing to the comparatively small head and large 

 abdomen, will I'endei- the recognition of this species easy. 



53. Tab anus astutus n. sp. 



Female. Palpi long and narrow, not incrassated at the base, dark yellowsn w^ith black 

 hairs ; face and cheeks grayish, Avith a slight yellowish tinge and gray hair ; front rather 

 broad, gray; callosit}- large, black, almost square; above it a somewhat lanceolate black 

 spot, almost or entirely disconnected from the callosity. Third antennal joint moderately 

 broad, and but little excised, still with a distinctly projecting upper angle ; the color is dark 

 reddish, black towards the tip; the segments of the annulate portion very distinct. Tho- 

 rax grayish black, well preserved specimens with very distinct whitish gray, partly yellow- 

 ish, lines ; pleura? gray. Abdomen grayish black, with three roAvs of whitish triangles 

 resting on the hind margins of the segments ; the lateral ones are oblique, obtuse angular, 

 with the outer angle prolonged towards the lateral margin. Venter grayish, with Avhitish 

 incisures, an indistinct dark longitudinal stripe in the middle. Legs brown ; the four hind 

 femora on the proximal half, the tarsi and the ends of the front tibias daik brown, nearly 

 black ; sometimes the legs are altogether black, except the proximal half of the tiljia3, 

 Avhich is brownish ; in such specimens the gray pollen on the femora, and grajish yellow 

 hairs on the femora and tibite, are more apparent. Wings nearly hyaline ; stigma brown ; 

 first posterior cell broadly open. Length, 10-13 mm. 



Hah. White Mts., N. IL (near North Conway, Aug. IG, 1874, two specimens taken by 

 me) ; Manlius, N. Y. (J. H. Comstock) ; Southington, Conn, (in July, W. II. Patton). I 

 have six females before me. 



The coloring and the markings of this species resemble T. mlcrocephalus very much ; 

 but the T. astutus is smaller, and the general outline is diffei-ent, as it has neither the small 

 head nor the large abdomen of tlie former. The most striking distinctive character, how- 

 ever, consists in the palpi, which here are long and narrow, and not so much incrassated at 

 the base as in mlcrocephalus. The front is much broader here, and the antennae have a 

 more distinctly projecting upper angle. The eyes " are not unlike those of mkrocephalus, 

 only the middle stripes more green than blue; the upper one very little marked " ; (note 

 taken by me from the living specimens). 



The old and faded specimens, which I consider to be females of T. vloax (see No. 20), 

 are not unlike this species ; they differ, however, in having the eye.s glabrous, and the lateral 

 abdominal spots more distinctly angular rather than triangular, that is, in having the 

 longest oblique side more distinctly excised in the middle ; the palpi are broader and more 

 knee-shaped at the base of the second joint ; the general outline of the body is different, 

 the thorax being comparatively longer and the abdomen narrower ; the third antennal joint 

 is somewhat broader ; the anterior of the three short veins, connecting the discal cell with 

 the margin, is straighter, not so markedly arcuate as it is in T. astutus and T. mlcro- 

 ce])halus. 



The males, of course, will be easier to distinguish, that of T. vivax having a large head, 

 wdth the large and small facets very distinctly differentiated ; while the unknown male of 

 T. astutus must belong to the group with the small heads and but little differentiated facets. 



