Dec, 1907.] New North American Tabanidae. 223 



margin to each abdominal segment. A conspicuous undenuded 

 dark patch or spot on the middle of the front. 



Female. Front rather wide, distinctly narrowed below, 

 ground color gray but with a dark colored undenuded patch or 

 spot on the middle of the front and another at vertex; frontal 

 callosity as wide as the front, shining black and connected with 

 an almost obsolete line above. Antennae brownish red, first 

 segment small, third widest at the base and gradually narrowed 

 to the annulate portion, thus there is no distinct tooth above, 

 basal portion longer than the annulate portion; palpi thick at 

 base, pointed below, rather dark colored. Thorax from above 

 with a gray margin which includes most of the scutellum, and 

 a dark colored disk which is furnished with green-reflecting scales 

 ■or hairs; wings hyaline, stigma yellowish, furcation of the third 

 vein with a short appendage ; legs black, bases of the front tibiae 

 and half or more of the basal parts of the middle and hind tibiae 

 yellowish. Abdomen black, each segment with a narrow pos- 

 terior gray border which expands into a small triangle on the 

 middorsal line. 



Females taken near Puerto Barrios, Guatemala, March 4, 

 1905. They were flying actively and now and then came to rest 

 ■on weeds and bushes. Fullv distinct from all species known t<^ 

 me. 



Tabanus limpidipennis n. sp. Length 16 to 18 milHmeters. 

 The eves are pilose but there is no ocelligerous tubercle. The 

 species therefore belongs to Osten Sacken's Atylotus and sug- 

 gests T. rienwardtii, but differing from that species the wings 

 are entirely hyaline. 



Female. Front about three fourths of a milhmeter in width, 

 slightly narrowed below, frontal callosity Hght brown, nearly 

 sqviare, and as wide as the front, a disconnected spot above, 

 nearly half way to the vertex. First antennal segment somewhat 

 produced above, brownish in color and clothed with black hairs; 

 third segment at extreme base brown, otherwise black, cut out 

 above so as to form a distinct but not an extended tooth at base. 

 Palpi thickened, yellowish and clothed with white hair. Thorax 

 in ground color dark, with nearly obsolete gray stripes and 

 clothed with a rather dense coat of elongate white hair ; legs red- 

 dish brown with the apexes of all the tibiae and entire tarsi black ; 

 wings hyaline. Abdomen dark brown above with a middorsal 

 row of gray triangles and a row of rather small rounded gray 

 spots on either side. 



Male. Head rather large, eyes with a distinct area of enlarged 

 facets above. Ground color of the abdomen more reddish brown 

 than in the female. In other respects the two sexes are alike. 



A male taken at Gaulan, Guatamala, January 21, 1905, and 

 a female taken in Guatemala in 1906. 



