6 THE NORTH AMERICAN SPECIES OF DROSOPHILA. 
26 minutes, respectively, but the beginning of these cases was not 
observed; 11 minutes is, however, probably unusually short for this 
species. 
Drosophila caribbea: Scissors movement, circling, licking, abdomen 
bent up underneath; no vibration seen. In copula about 10 minutes. 
Drosophila funebris: Scissors movement, licking, abdomen bent up 
underneath; no circling or vibration. One wing is sometimes slowly 
spread to a right angle with the body and then relaxed, without vibra- 
tion. This motion, which occurs in some other species, I have called 
“waving.” In this species, unlike any of the preceding, the female 
spreads her wings apart before mating, and the male normally does 
not attempt to mate until she does spread them. After she spreads 
them he may mount, and copulate as he does so; he may continue 
licking, or he may partially mount and not copulate. Even if mating 
does not occur, the female holds her wings spread apart for about a 
minute. I removed the wings from two females and placed males 
with them. In this case the males seemed not to wait for the females 
to spread the stumps of wings that remained, but attempted to 
mate before that happened. In copula 13, 14, 16, 18, 18, 19, 20 
minutes. 
Drosophila hydei: As in D. funebris. Copulation may be repeated 
within 30 minutes. In copula 1, 1, 1, 1, 2, 2, 2 minutes. 
Drosophila immigrans: Scissors movement, waving with both wings 
at once, licking, male genitalia go up underneath; no circling or vibra- 
tion; female does not spread her wings. The position of the legs of 
copulating males of this species has been observed in several cases, 
and has been found to be quite variable, as it probably is in all species. 
In copula 15, 53, 54, 55 minutes. The female is very restless for about 
the first 10 minutes. 
Drosophila lutzii: No scissors movement, vibration, or circling seen. 
The male stands behind the female, with his head under her wings, 
and often stays thus quietly for some time. Then he pushes up 
against her wings jerkily with his head, at the same time bending his 
abdomen around to one side. During this act his long axis is not 
quite parallel to that of the female, and the abdomen comes around 
the shortest way. The female spreads her wings, and the genitalia 
come together at almost the same time. The male then mounts, his 
final position being that which is usual for the genus. Two copulations 
timed, each lasting about 1 minute. 
Drosophila melanica: Not observed in detail, but scissors movement 
and licking seen. 
Drosophila nebulosa: Vibration, scissors movement, licking, but not 
much of any of them. The male stands facing the female, in front of 
her and a little to one side. He waves the wing on the side toward the 
female several times rapidly, at the same time bending his abdomen 
