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‘slight difference in age. The lateral depression of this 
batch of eggs was puzzling, but after a number of eggs had 
been repeatedly examined it was found that it was placed 
well up towards the micropylar area, but was somewhat 
obscured by the depressions, described as being characteristic 
of T. bistortata, being often placed in close proximity there- 
with. These eggs, like those of many other species that 
are laid in crannies, &c., e.g. Orrhodia, &c., appear to be 
capable of much modification in shape by pressure, the moth 
pushing the egg into acranny, and the soft egg being affected 
more or less by the pressure, and so becoming somewhat 
similar in shape of the cranny into which it is pushed. 
It is very probabie that the eggs of these two species have 
never before been examined side by side under the micro- 
scope, owing to the different dates at which the insects 
usually appear. The chance of doing so now is due to Mr. 
A. Bacot, who, by forcing the pupz of T. crepuscularia, 
brought out the imagines at the same time that those of 
I’. bistortata were appearing in the breeding-cages. By this 
means also he obtained pairings between ? T. bistortata 
and 3 T. crepuscularia, although it appeared that they would 
not cross in any other way. This is, of course, exactly the 
parallel to Dr. T. A. Chapman’s experiment when he forced 
Amphidasys betularia to appear in March, and then obtained 
pairings between that species and A. strataria, and not only 
obtained fertile ova but bred the hybrid imagines. 
Mr. Barrett suggested that the iridescence observed was, 
perchance, due to the ova being near the point of hatching, 
but Mr. Tutt said that the ova were laid on the same day as 
they were examined, and added in reply toa further question 
that he did not know whether the eggs were the product of 
one female of each species or not. Mr. Barrett did not see 
how the mere pairing could affect the shape and form of the 
ova, but thought that the intermediate character of these 
cross-fertilised eggs merely showed that the slight difference 
of shape between those of the two so-called species arose 
from individual variation. 
Referring to the alleged occurrence of Tephrosia biundu- 
larva in Morayshire, Mr. Tutt said that it had been stated, 
on the strength of a specimen in Mr. Adkin’s possession, 
and another in Mr. Horne’s, that T. biundularia was found 
in Altyre Woods, in Morayshire. He had examined Mr. 
Adkin’s specimen, and so also had Mr. Southand Mr Adkin. 
Mr. South and himself were all inclined to refer it to T. 
crepuscularia (bistortata). He now exhibited Mr. Horne’s 
