1916], North American DrosophiUdcE 341 



cheeks about one-sixth greatest diameter of eyes. Cheeks yellow, a 

 brown spot on each side, just above and behind vibrissa. Eyes with 

 yellow pile. 



Six acrostichal rows; no prescutellars. Dorsum of thorax dull 

 reddish yellow, with a pair of darker indistinct longitudinal stripes and 

 dark areas on and behind the humeri. Scutellum reddish yellow. 

 Pleura pale yellow, a reddish line running forward from base of wing; 

 darker above this line. Legs pale yellow. Preapical bristles only on 

 third tibiae, apicals only on second. 



Abdomen dull reddish yellow, with posterior black bands on first 

 four segments. 



Wings clear. Costal index about 1.9; 4th vein index about 2.0; 

 5x index about 1.8; 4c index about 1.4. 



Length body 2mm., wings 2mm. 



Type and ten paratypes, Adjuntas, P. R., June 8-13, 1915 

 (Lutz and Mutchler). Two specimens, San Francisco Mts., 

 San Domingo, (Busck). The females agree with the above 

 description. Some specimens are a little smaller and have 

 the dark marks on front, thorax and abdomen practically 

 invisible. There are intermediate specimens, and I suppose 

 that the difference is due to age. 



The species is distinct from other described species in the 

 color of the thorax. Its most unusual peculiarity is the fewness 

 of the apical and preapical bristles, in which it resembles 

 D. quadrata n. sp. The large hairy third antennal joint is also 

 noteworthy. 



Drosophila quadrata, n. sp. 



cf. Arista with six branches above and three below. Antennas 

 brown. Front one-half width of head, wider above; pale yellow. 

 Second orbital not distinguishable from neighboring hairs. One large 

 vibrissa, other oral bristles reduced practically to hairs. Carina low 

 and narrow, face broad and excavated on each side of it; face yellow. 

 Proboscis yellow, palpi dark brown. Cheeks yellow, their greatest 

 width about one-fifth greatest diameter of eyes. Eyes with yellow 

 pile. 



Eight rows of acrostichal hairs ; no prescutellars ; the anterior dorso- 

 central bristles are only a little behind the suture. Dorstun of thorax, 

 scutellum, pleuree and legs dull brownish yellow. There is a dark brown 

 stripe on the pleura extending as a straight band from just under the 

 haltere almost to the neck. Below this stripe the pleura is paler. 

 Apical bristles only on the second tibiae, preapicals only on the third. 



Abdomen yellow, each segment with a dark brown posterior margin. 



Wings clear; costal index about 1.0; 4th vein indejs; about 5.5; 

 5x index about 6.0; 4c index about 5.0. , 



Length body 13/4mm., wings 2mm. 



