D. hydei ssp. yucatanensis, from Yucatan, is descr. Hybrids with D. h. hydei are fertile and displayed no marked abnormalities in the salivary chromosomes. 17 morphological and physiological character differences between D. virilis americana and D. v. virilis are descr.; they include body and eye color, clouding of wings, body and carina shape, eye size and pile, pupa case color, manner of pupation, etherization time and texture of viscera. The 2 subspp. of virilis can be crossed and the hybrids of both sexes are partially fertile when crossed inter se or back to either parent subspecies. Salivary chromosomes show some major inversions and loose pairing. The gonial chromosome group of virilis consists of 5 pairs of rods and a pair of dots; that of americana [female][female] of 1 pair of rods, 1 pair of dots, and 2 pairs of Vs. D. v. americana has been taken in Ohio and Tennessee; D. virilis is native to Japan and the Far East.[long dash] Other crosses of diverse types in Drosophila are reviewed and considered in connection with the 2 subspp. crosses herein discussed.