AMERICAN DIPTERA. 305 



Metapog'on puiictipennis. 



Metapogon punctipennis Coquillett, Proc. Ent. Soc. Wash., VI, 

 182, 1904. 

 "(^ 9 • — Length 7 mm. — Black; the first two segments of the antennse, 

 the tibiae, bases of tarsi and extreme apices of femora reddish-yellow; 

 the halteres pale yellow; all hairs and bristles white. Antennal style 

 about one-fifth as long as the third joint, mystax ascending about 

 three-fourths the height of the face. Mesonotum grayish pruinose, 

 marked with a submedian pair of black vittse which extend from the 

 front end three-fourths of the distance to the scutellum, also with a 

 pair of blackish spots on either side separated by the suture; hairs of 

 mesonotum very short and sparse; mesopleura, pteropleura and sterno- 

 pleura bare; scutellum flattened, nearly bare, thinly grayish pruinose 

 bearing a subapical pair of stout bristles. Abdomen polished; first 

 segment gray pruinose on the base and sides, second with a gray 

 pruinose fascia near the base and an oblique spot in each hind angle, 

 segments 3-6 each with a gray pruinose fascia at the base connected 

 at either end with an oblique spot that extends to the hind angle of 

 the segment, the spots on the segment of the female separated from 

 the fascia; each of these fasciae are rather strongly narrowed in the 

 middle of the posterior side; a gray pruinose spot on either side of 

 the seventh segment. Wings hyaline; veins and cross- veins at base 

 of the discal, posterior and submarginal cells, distinctly, but rather 

 narrowly clouded with brown; the small cross- vein nearly two-thirds 

 the length of the discal cell." 



Type. — U. S. N. M., Cat. No. 7955. A single specimen of 

 each sex. 



Habitat.— Organ, N. M. (T. D. A. Cockerell). 



PLESIOMMA. 



Plesiomma Macquart, Dipt. Exot., I, pt. 2, 54, 1838. 



Strikingly different from all other Asilids in that the large 

 eyes of both males and females are nearly contiguous above, 

 or noticeably approaching that condition ; thus the face is very 

 broad below and gradually narrows upwards so that the face 

 and front together form a triangular area. Antennas are sit- 

 uated on a line with the middle of the eyes or a trifle above: 

 segments 1 and 2 subequal, cylindrical, with bristles above 

 and below; segment 3 subequal to segments 1 and 2 taken 

 together, more or less oval, with short forward directed bris- 

 tles on its upper side; style distinct, more or less bristles-like. 

 Ocelli borne on a slight elevation and vary in their location 



TRANS. AM. ENT. SOC, XXXV. (39) AUGUST, 1909 



