SYSTEMATIC ACCOUNT. 75 
Datura and melon flowers in Cuba, and in morning glories in Costa Rica and 
Florida. Dr. Metz reports it common in cotton flowers in Jamaica. We 
have reared adults from the decaying petals of such flowers, and in addition 
Dr. Metz has bred the species on tomato fruit. 
The description of Drosophila mauiensis Grimshaw, from Hawaii, sug- 
gests that that form is probably similar to this and to D. tristani. Its habits 
are not recorded. 
The mating habits of D. lutzii are recorded elsewhere in this paper. 
Drosophila tristani, new species. 
Q@. Arista with five short branches above and three below. Antenne dark brown. 
Front over one-third width of head, wider above; black. Second orbital about one-sixth 
other two. Only one prominent oral bristle. Carina very broad and flat; face black. 
Cheeks dark brown; their greatest width about one-fifth greatest diameter of eyes. Eyes 
with short pile. 
Acrostichal hairs in eight rows; no prescutellar bristles. Mesonotum and scutellum 
moderately shining black. Pleure black. Coxe and femora dark brown, tibiz and tarsi 
pale yellowish-brown. Apical and preapical bristles on first and second tibie, preapicals on 
third. 
Abdomen shining black. 
Wings clear. Costal index about 2.8; fourth-vein index about 1.8; 5x index about 1.3; 
4c index about 0.9. 
Length body 1.8 mm.; wing 2.0 mm. 
Type, San Jose, Costa Rica, March 1915, in the corolla of an Ipomea 
flower. The species is named for Professor J. F. Tristan, who was acting 
as my guide when the type and only specimen was collected. 
Drosophila alfari, new species. 
o'. Arista with about five branches above and two below. Antenne brown. Front 
over one-third width of head, wider above; dark brown, lighter below. Second orbital 
about one-fifth other two. Only one prominent oral bristle. Carina broad and flat; face 
brown. Cheeks brown; their greatest width about one-fourth greatest diameter of eyes. 
Eyes with short pile. 
Acrostichal hairs in eight rows; no prescutellars. Mesonotum and scutellum dark 
brown, slightly shining. Pleurze dull brown. Legs pale yellow. Preapical bristles on all 
tibiz, apicals discernible only on second pair. 
Two basal segments of abdomen dull brown; third to fifth segments brownish yellow, 
with posterior interrupted brown cross-bands. 
Wings clear, veins yellowish brown. Costal index about 3.6; fourth-vein index about 
1.6; 52 index about 1.2; 4c index about 0.6. 
Length body 2.2 mm.; wing 2.3 mm. 
Type and 17 paratypes, San Jose, Costa Rica, March 1915, in the corollez 
of a large species of Datura, in which were also many specimens of D. flore. 
The species is named for Dr. A. Alfaro, of the National Museum at San Jose. 
The females among the paratypes agree with the above description of 
the male. There are some specimens, of both sexes, in the lot that have 
some yellow on the two basal segments of the abdomen. 
Group E. 
Preapicals evident only on third tibia; pleursee or mesonotum striped; carina narrow. 
Drosophila prognatha Sturtevant. 1916. Ann. Ent. Soc. America, 9, 340. 
3&, 9. Arista with about six branches above and two below. Antenne yellow, third 
joint very long and covered with yellow hairs. Front over one-third width of head; dull 
yellow, ocellar dot brown. Second orbital one-fourth other two. Vibrisse long, other 
oral bristles short. Proboscis prominent and projecting forward. Carina short, low, 
narrow, and confined to upper part of face; face dull yellow. Cheeks yellow, a brown spot 
on each side, just above and behind vibrissa. Greatest width of cheeks about one-sixth 
greatest diameter of eyes. Eyes with yellow pile. 
