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 activelv and now and then came to rest 
on weeds and bushes. Fullv distinct from all species knowm to 
me. 
Tabanus limpidipennis n. sp. Length 16 to 18 millimeters. 
The eyes are pilose but there is no oeelligerous 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 millimeter in width, 
slightly narrowed below, frontal callosity light brown, nearly 
square, 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. 
