276 
NORTH AMERICAN MYRMOSIDAE 
Lower California: Cape St. Lucas, [Type, American Entomological 
Society, no. 1894]. Xew Mexico: Albuquerque, no date, 2 d', July 16, 
1902, 1 d, (E. J. Oslar), [Cornell University]. Colorado: Durango, 1 d, 
(E. J. Oslar), [Cornell University]. 
Brachycistis (Brachycistis) stygia new species 
c?". Entirely coal black, with white pubescence; wings hyaline, infiiscated 
bejmnd the stigma, especially along the costal margin, becoming clearer again 
toward the margin. Length, 1.3.5 mm. 
Head poli.shed, shining, with sparse but not small punctures; ocelli smaller 
than usual, not very prominent, the posterior pair removed by twice their 
diameter from the eyes; measurements: .25 mm., .5 mm., .6 mm.; a faint, 
transverse impression behind the posterior pair, but no longitudinal impressed 
line between them; forehead above the antennae simple; inferior margin of 
each antennal socket thin, without a tubercle, closely short-hirsute; clypeus 
not tuberculate, thickly punctured toward the margin, which is thickened, 
emarginate, and slightly raised; mandible with the inner two teeth strong 
and blunt, of equal size, a falcate blunt carina extending from the inner one 
to the base; gular orifice small, its margin removed from the eye by consid- 
erably more than the length of the ultimate segment of the labial palpus, 
and from the globular swelling at the condyle of the mandible by consider- 
ably more than the apparent diameter of the same. Antennae strongly 
crenulate toward their apices. 
Pronotum with prominent but rounded humeral angles, these and its dorsal 
surface closely coarsely punctured, its sides sparsely punctured; mesonotum, 
disc of scutellum, and postscutellum with sparse, but coarse punctures; 
lateral grooves distinct; sides of the scutellum and postscutellum closely 
punctured; mesopleura closely punctured, the punctures becoming sparse on 
the sternum, which is separated from the pleura by fine impressed lines, oli- 
solete both anteriorly and posteriorly; surface of each mesopleurum swollen 
and uneven, with a small but deeji pit on the posterior summit of the swollen 
part; superior surface of the propodeum mostly impunctate, with a broad 
median depressed channel, the posterior part of which, as well as the posterior 
surface on either side, is sculptured with large, shallow, irregular depressions; 
dorsal face of the propodeum separated from the posterior by a transverse 
carina; the lateral angles prominent, sharp, strongly and closely punctured, 
the punctures becoming obsolete on the depressed lower part of the sides; the 
posterior face of the propodeum almost vertical, somewhat hirsute. 
^^'ing venation as shown in figure 7 ; the veins and stigma piceous. 
Legs armed as described for crassa. 
Abdomen sessile, the basal segment short, broad, and thick, enlarging di- 
rectly from the base without any anterior neck, separated by a moderate con- 
striction from the second ventral; the latter with a convex horizontal surface 
only, without a transverse carina; first segment coarsely and closely, but 
dorsally sparsely and finely punctate; remaining segments finely and sparsely 
punctured; pygidium truncate, its sides strongly margined, and with a median. 
