eau 
with a group of the European Vanessas. These are probably as 
nearly allied to one another as are the Acrwas and Eupleas, 
but though presenting in common the characteristic Vanessa 
facies, they are distinguishable from one another at a glance. 
There is therefore in all probability some other factor at work in 
bringing about the resemblance between the members of these 
tropical groups besides that of mere affinity. 
Certain other points remain to be noticed before we can be quite 
sure that we are in possession of all the data needful for an explan- 
ation. It is no doubt natural to enquire as to the comparative 
numbers of the various forms concerned. The answer here is 
perfectly definite; sometimes one ofa pair, or several of an assem- 
blage showing a common aspect, is much rarer than the rest; also 
it often happens that some one form of the combination is much 
more abundant than any other constituent of the association. But 
on the other hand there are plenty of cases in which most, if not 
all, of the mutually resembling forms are common. This fact was 
a great puzzle to BATES, as it plainly did not fit in very comfort- 
ably with his theory. On this point I shall have more to say before 
concluding. 
Once more; we find that these mimetic assemblages or combin- 
ations, so to call them, are not sharply marked off from one another, 
but show frequent passages from one to another by almost imper- 
ceptible gradations. Take for instance such a series at that now 
shown on the screen, which might be considerably extended. The 
Papilio at the top (P. SA and the /Zeliconius at the bottom 
(17. venusta) are each of them members of a large mimetic asso- 
ciation. The yellow patch on the forewing is common to both, 
though its shape and position on the wing show differences; in 
other respects the patterns exhibit much divergence. But the three 
intermediate Butterflies (Huterpe approximata, E. bellona, and 
E. nigrina |underside]), which are all Pierines, show an array of 
connecting links which enables us to pass by an easy gradation 
from one extreme of the series to the other. This is only a single 
example of a state of things, which is constantly to be met with i in 
the lepidopterous fauna of tropical regions. 
What then have we learned in the course of this brief survey? 
The points may be summed up as follows : 
1. The cases of resemblance between distinct kinds of Insects are 
very numerous — too numerous to be accidental. 
2. These resemblances are to a very great extent independent of 
