440 Experimental Zoblogy 
was first developed in the male and was then transferred to 
the individuais of the other sex. 
There are serious objections to the theory of sexual selection, 
some of which Darwin himself has considered. He points 
out, for instance, that his theory demands “powers of dis- 
crimination and taste on the part of the females which will 
at first appear extremely improbable.”” The few instances that 
Darwin gives to show that such discrimination may really exist 
are far from convincing. Amongst domesticated animals there 
is very little evidence that can be brought forward to support this 
view, and much that is opposed to it. It must be borne in mind 
that even although the female may be excited by the presence of 
the male or by his antics and demonstrations, it is essential 
that she consistently select the most adorned in order that any 
result may follow. ‘Tegetmeier observed that a game cock, dis- 
figured by being dubbed and with hackles trimmed, was accepted 
by the females. 
Mayer has recently carried out some experiments with the 
moth Callosamia promethia that show very clearly that the 
adornment of the male or of the female is not a factor in the 
selection by the other sex Five females were placed in an open- 
mouthed glass jar covered by netting. Five males, liberated one 
hundred feet away, flew to the jar. If the jar was inverted so 
that its opening was closed, the males did not approach, although 
the females could be seen through the glass. It appears, there- 
fore, that the males find the female by the sense of smell, not by 
sight. 
Some females were inclosed in a box with an open chimney. 
The males flew to the chimney, although the females were not 
visible. When the abdomen of the females were cut off the 
males flew to these, and paid no attention to the winged body. 
Wherever a female has stood for some time, the males are at- 
tracted to that spot. If the antenne of a male are cut off, he 
does not go to the female. These experiments also show that 
the male finds the female by a sense of smell, and not by 
vision, although the female is highly ornamented. 
