CAPTURES AND FIELD REPORTS. 913 
which I identify as Polydrosus micans. My first impression of a 
startling difference between the male and female of mzcans was 
momentary only, but the possibility of a hybrid between two such 
dissimilar species appeared to warrant further investigation, and the 
two pairs were accordingly placed in separate glass-tubes and taken 
home. On my arrival home I found that one pair had separated, and 
the male had apparently lost all interest in his companion; but in 
the other tube attempts at copulation continued from 7.30 to 
11.30 p.m. uninterruptedly, but at the end of that time I shook the 
tube up, which separated the insects, and no further attempts were 
apparently made. In the morning the two were at different ends of 
the tube, each apparently ignoring the presence of the other. I am 
satisfied from a careful examination through a strong lens whilst the 
attempts were being made that copulation did not actually occur. 
The male organ was for the greater part of its length too inflexible to 
allow of the penetration of the female organ of the different species, 
the angle was not right. Save for this, the violent and repeated 
efforts of the male could only have ended one way. If two insects 
sexually ripe but of different species are isolated together, the 
abnormal may occur, but it did strike me as very strange that 
attempts of this sort should be made right out in the open, where 
one would have thought the females of the green Polydrosus would 
have far out-numbered the females of micans.—C. G. Doventy; 
27, South Molton Street, W., and Eghams Farm, Beaconsfield, 
June 22nd, 1909. 
[It is frequently noticed that Coleoptera of two distinct species 
are in the position of copula without copulation subsequently oc- 
curring.—D. 8.] 
CAPTURES AND FIELD REPORTS. 
ABUNDANCE OF PIERIS BRAssIc#.—During the last three weeks 
of May Pieris brassice daily increased in numbers until the end of 
the month, when in this part of south-east Essex a perfect swarm 
occurred, but nearly all that I observed were males, it was only 
during the last few days of May that the females appeared in any 
number; until then I had not seen half a dozen, while the males 
were flying in hundreds. Pieris rape was equally prolific, but the 
sexes of more equal proportion.—F. W. Fronawxk; July, 1909. 
PROPORTIONATE NuMBER OF SEXES OF THANAOS TAGES.—Although 
the males of most or all species of butterflies appear on the wing 
some days before the females, I think the following note is worthy of 
record, considering the date of observation and the fact that I noticed 
the species flying over the same spot six days previously. On May 
21st last I captured forty-five Z'. tages over a small patch of rough 
ground about fifty yards long by ten yards wide; out of this com- 
paratively large number only one was a female, which deposited a 
quantity of eggs. Last year, on the evening of June 10th, in the 
corner of an adjoining field, I found this butterfly in such abundance 
at rest on the heads of grasses that in some instances there were as 
