154 



Psyche 



[December 



stock collected at Lakeland, Fla. (C. W. Metz). Type deposited 

 at the American Museum of Natural History, New York City. 

 The gonotypes are not descended from the type, but the whole type 

 series is known to be descended from a single female. 



Other specimens examined: Randolph, N. H. (Miss H. Daniels) ; 

 Cold Spring Harbor (C. W. Metz), Staten Island (F. Schrader), 

 N. Y.; Rochester, Minn. (L. Huckfield); Richmond, Va.; Macon, 

 Ga. (G. L. Carver); Palm Beach, Fla. (B. B. Horton); Kushla, 

 Ala.; Fayetteville, Ark. (B. Schwartz); Port Limon, Costa Rica. 



Examination of genitalia shows that D. melanogaster has at least 

 the following range : Nova Scotia to Oregon, California, and Florida; 

 Cuba, Porto Rico, Costa Rica, Panama; Holland; Australia. 



D. simulans and D. melanogaster may be crossed, though only 

 with difficulty. The hybrids so far obtained have apparently all 

 been sterile. They are obtained most easily from the mating of D. 

 melanogaster female by D. simulans male; and from this cross only 

 females are ordinarily produced. It was the discovery of this fact 



Fig. 1. 1, External male genitalia of Drosophila melanogaster Meig., from cleared 

 material collected in Minnesota; 2, external male genitalia of Drosophila simulans 

 sp. nov., from cleared material mounted in balsam. Genotype. 



