102 THE NORTH AMERICAN SPECIES OF DROSOPHILA. 



The difTerences between this species and the two preceding ones that are 

 available in livinp; material are discussed under D. repleta. Its chromosomes 

 are referred to on page 39. This form may be bred on banana. 



Drosophila ramsdeni Sturtevant. 1916. Ann. Ent. Soc. America, 9, 328. 



o"', 9 . Arista with alxnit four branches above and two below. AntenniE pale yellow, 

 third joint reddish brown above. Front pale yellow, three brown spots on each orbit and 

 one around each ocelhis. Second orbital one-fourth size of other two. First orbital three 

 times size of second. Carina large, broad, sulcate. Face and cheeks yellow, a brown spot 

 just below carina and one just below each eye. Eyes pilose. 



Acrostichal hairs in eight rows; no prescutellars. Mesonotum light gray, each hair and 

 bristle arising from a dark-brown spot. Between the dorsocentrals these spots are fused 

 into a pair of irregular longitudinal stripes. Scutellum light gray, basal pair of bristles 

 arising from brown spots. Pleurae dark brown above, pale yellow below. Legs pale yellow, 

 tips of femora and bases of tibiae brown. Apical and preapical bristles on first and second 

 tibiae, preapicals on third. 



Abdomen yellow, each segment with a dark-brown cross-band, which is broadly broken 

 in the mid-dorsal hne. 



Wings clear; veins pale brown, with dark-brown spots at tip of first vein and at junction 

 of first and second veins. Costal index about 2.6; fourth- vein index about 2.0; ox index 

 about 1.2; 4c index about 1.1. 



Length body 2.5 mm.; wing 2.5 mm. 



Specimens examined: Guantanamo, Cuba (C. T. Ramsclen, type ma- 

 terial). 



This species has been bred from pineapple. 



The chromosomes, reported bj^ INIetz (1916, Amer. Nat., 50), are described 

 on page 39. 



Drosophila alabamensis Sturtevant. 1918. Journ. N. Y. Ent. Soc, 26, 38. 



Arista with five branches above and one below, ^^ntennae large, brown; third joint 

 large, oval, dark. Front about one-half width of head, wider above; brown, triangle and 

 orbits grayish. " Second " orbital over one-half other two, placed a trifle below third. 

 Only one prominent oral bristle. Carina very small, confined to upper part of face; face 

 light brown. Proboscis brown, palpi dark brown, large. Cheeks brown; their greatest 

 width about one-third greatest diameter of eyes. Eyes with short pile. 



Acrostichal hairs in six rows; no prescutellar bristles. Mesonotum dull brown; humeri, 

 median stripe, pair of stripes in dorsocentral rows, and posterior pair of stripes outside the 

 latter and joining them at the suture, grayish. Scutellum brown, with grayish border. 

 Pleiu^ dull brow^n. Legs yellowish brown. Apical and preapical bristles on first and 

 second tibiae, preapicals on third. 



Abdomen dark dull brown. 



Wings clear. Costal index about 2..3; fourth-vein index about 2.3; 5x index about 2.0; 

 4c index about 1.3. 



Length body 2.3 mm.; wing 2.5 mm. 



Specimen examined: Kushla, Alabama, April 9, 1915 (type). 



Drosophila bilineata Williston. 1896. Trans. Ent. Soc. London, 409. 



"cT". Front of equal width, not widened above; opaque velvety black, the orbits and a 

 slender median Une opaque yellowish-grey. Face light yellow, on the sides above dusted 

 like the frontal orbits. Cheeks and the dilated palpi black, the cheeks yellow behind. 

 Face distinctly receding, carinate in the middle. Antennae brownish-yellow or brown, the 

 third joint more than twice as long as wide; arista with about five rays above and three 

 below. Occiput black above. Mesonotum and scutellum opaque deep-brown, the former 

 with two narrow stripes, not reaching the hind margin, and appearing like continuations of 

 the frontal orbits. Pleurae light yellow. Abdomen oval, not elongate; opaque deep-brown 

 or black, the fifth segment, except sometimes a small spot in the middle, the remainder of 

 the abdomen [sic), and the narrow lateral margin of all the segments yellow. Legs light 

 yellow. Wings greyish hyaUne; ultimate section of the fourth vein not twice the length 

 of the penultimate section. Length 1| mm. 



" Three specimens. St. Vincent." 



