Sept., 19 M.] Alexander: Tanyprexina and Mix.istoceka. 209 



white; the prnescutuni with deep impressed lines extending from the 

 pseudosutiiral fove.-c caiidad to the transverse suture; a dark brownish 

 black mark at tiie humeral angle of the sclerite extending ventrad onto 

 the pleurre ; scutum dark brown, a little paler medially ; scutcUum anti 

 postnotum brown, the latter a little paler on the sides. Pleurae pale, 

 yellowish white, with a broad brown stripe extending from the 

 humeral angle of the pr?escutum ventrad and caudad across the meso- 

 pleurae, splitting near the base of the fore coxa, the anterior fork 

 broad suffusing the sides of the mesosterna and the base of the 

 mcsocox.T. Halteres long and slender, the stem pale brown, the knob 

 dark. Legs with the coxa; pale except the mesocoxa: as described 

 above: fore legs with the trochanters having a decided green caste, 

 femora dark brown, the base pale, tibia; with the base broadly pale, 

 about equal in width to the black apical ring, a rather broad white 

 subterminal band; metatarsus dark brown, the white medial band a 

 little broader than the dark basal ring, remainder of the tarsi white. 

 Hind legs with the femora brown, the tibia; with the basal three- 

 fifths dark brown, the remainder snowy white excepting a broad dark 

 brown tip; metatarsus white except the broad brown base and apex; 

 remainder of tarsi pure white. Wings usually with a light brown 

 tinge, in some more nearly hyaline, and the costal cell brown ; stigma 

 dark brown, the cord more indistinctly seamed with brown. \'enation 

 as in fig. i: Rs oblique, short and straight; the deflection of R,,. 

 arcuated, forming a V with the end of the sector; 7?, short and show- 

 ing a tendency to atrophy ; basal deflection of R,^^ lacking. 



Abdominal tergites 2 to 4 brown with a broad white basal blotch 

 on the sides and a broad white blotch on either side beyond the middle, 

 the extreme lateral margin of the sclerite narrowly blackish brown; 

 apical tergites uniformly dark brown. Sternitcs dull yellow, the 

 ovipositor reddish brown. 



Distribution.— British Guiana, Upper Potaro River. July 17, 1911. 

 (Crampton.) Specimen, a female, in the collection of the .\mericnn 

 Museum of Natural History. Brazil, Manaos (Mann). Specimen a 

 female in the collection of Mr. C. W. Johnson. 



Tanypremna longissima Enderlein. 



1912. Slegasmonotus loiuiissimiis lindcrlcin ; Zool. Tahrb., vol. ^2. nt. i. 



