144 NEW YORK STATE MUSEUM 



I can not distinguish the American specimens from those 

 which I have from Europe. The marks upon the abdomen of 

 the male are quite variable; in some specimens they are simply 

 spots on the posterior lateral margins of the segments, in others 

 they form a broken median dorsal stripe, and in still others they 

 are almost entirely wanting. The male genitalia in some speci- 

 ments are somewhat brownish. The dark spots upon the wing 

 are arranged as follows : One on the humeral crossvein, one on 

 the discal crossveins, one at the tip of B 1? and one at the tip of 

 R 4 4. 5 . The paler spots are larger than the darker ones. There 

 is one below the tip of ~R+ 5 , one in the middle of cell R 4 4. 5 , a 

 small one at the tip of the median, and one at the tip of each 

 branch of the cubitus, one or two in the median cell and several 

 in the anal cell. The fork of the cubitus is also clouded. Some 

 of these spots 1 are not always distinct because the color is due 

 to the darker colored hairs, which are easily rubbedi off. The 

 wing of the female is usually darker than that of the male. 

 (P1.27, fig.6.) Specimens from New Jersey, Illinois, Ithaca, N. Y., 

 South Dakota. 



Osten Sacken, in a note in his catalogue of the North American 

 Diptera (1878), first calls attention to the fact that T. a n n u- 

 1 a t u s ,Say and <m o n o 1 i s Linn, may be synonymous. I have 

 compared the North American species, which agree perfectly with 

 Say's description, with specimens of m o n i 1 i s from Europe, 

 and I can find no differences. For the sake of comparison, Say's 

 description is given below. 



Tanypus. annulatus Say 

 Jour. Ac. Nat. Sc. Phil. 3:15. 1823 



Tergum annulate with dusky; wings clouded with dusky and 

 with three or four blackish points. Inhabits Pennsylvania. 



Head and stethidium red-brown; thorax, the anterior dilated 

 line with a 'brown line along its middle ; feet white, thighs having 

 an annulus near the tip, and tibia with one at base and two near 

 the tip fuscous; wings with large, obsolete, dusky, spots .or 

 clouds, and three or four (black-brown points, of which two are 

 toward the middle of the wing, and the remainder on the costal 

 margin near the tip; tergum segments with a dusky annulus at 

 their bases. Length about 3/20 in. Male. 



