( xe”) 
together. Instead of 3 10 uniting with either of the 297 or 
8, he was in coiti with the one of the three which most nearly 
resembled himself. 
It is obvious that my material is not enough to do more 
than suggest the interest that could be got from a large col- 
lection of hundreds of specimens made without prejudice, 
both of single specimens and of pairs in coité. This species 
is an ideal one for such a collection, it is conspicuous and 
easily caught, it occurs in numbers in suitable open grassy 
places, and the pairs are easily seen 2m cot? on grass stems. 
Moreover, it is small, and yet well marked. Had we such a 
collection we could estimate mathematically the chances of 
one type pairing with its own rather than with another, 
according to the relative abundance of the different types; 
and then we should soon see whether the pairing was according 
to mathematical chances, or by selection. 
In this connection it is interesting to note that on Bugalla 
Island on Jan. 14, 1912, specimens of every type were taken, 
and a single pair taken on that day was the worst matched of 
all my pairs ! 
This just shows how much we want a large amount of 
material from one locality. It may be said How can one moth 
select another of a pattern like itself? Even if it can see the 
pattern of its mate it does not know what its own pattern is 
like. It must be, if there is anything in the sexual selection 
amongst varieties, a problem of the same nature as Why does 
one individual know that another of the same species is its proper 
mate? It seems probable that the answer is, in the case of the 
little Syntomid we are discussing, that scent has much to do 
with it, and that variation in pattern is correlated with varia- 
tion in scent. A lucky observation which I made on Bugalla 
Island, Oct. 25, 1912, has some bearing on this matter. A 
male moth, of the species we are discussing (Epitoxis albicincta), 
was sitting on a grass stem perfectly quiet and unconcerned, 
but a male Acraea terpsichore, L., form ventura, Hew., ina state 
of great sexual excitement, was endeavouring by every means 
in its power to effect coitus, frantically passing the tip of its 
abdomen round about the abdomen of the moth in every 
direction, and obviously trying to pair. Both these specimens 
