Butterflies of Protected Genera. 421 
as the mimicked species, as it possesses a pseudo scent-gland, 
which may reasonably be considered as adding to its protec- 
tive or uneatable character, and which is absent in LH. Bremert. 
We thus have the ‘ mimicking’ very much more abundant 
than the ‘ mimicked’ species, which is contrary to the usually 
observed phenomena, though Fritz Miiller has recorded some 
similar exceptions as occurring in Brazil, and the same ob- 
server has also endeavoured to show that there is an advantage 
in two nauseous species resembling each other, as occurs be- 
tween two American species, both of which belong to genera 
which are protected from birds and other enemies by distaste- 
ful qualities. Such propositions are, of course, at present 
hypothetical, and are at least supplementary to the carefully 
observed facts on which Mr. Bates originally disclosed and 
argued the admirable doctrine of ‘ mimicry,’ which accounted 
for the strange external resemblances, long known to ento- 
mologists, which existed between insects belonging to distinct 
genera, families, and even orders, between which there was 
no real affinity”? (Rhop. Malay. p. 33). 
It seems to me, on carefully considering the foregoing ex- 
tract, that the author has mixed up two very distinct things 
as being ‘“‘ at present hypothetical,” viz. (1) the statement 
that a mimicking species is sometimes more abundant than 
its model, and (2) the demonstration that there would be an 
advantage in one distasteful species resembling another dis- 
tasteful and more abundant species. ‘The former is a simple 
record of observation and involves no hypothesis whatever. 
Thus in the case of such mimetic pairs as Mechanitis lysim- 
nia and its imitating Leptalis, and Papilio nephalion and its 
mimicking Euterpe tereas, there can be no doubt as to which 
is the model; and Fritz Miiller has observed that the models 
are, in these instances, “ hardly more common” or are much 
rarer than the mimics. This was at least the case in the part 
of Brazil where he made this observation *. 
The second “ proposition” is hypothetical only to the ex- 
tent of our not having any direct observations upon the inex- 
perience of young insectivorous birds and other enemies. If 
we grant, as appears to me most probable, and as Fritz 
Miiller and Mr. Wallace have admitted, that a certain number 
of individuals of distasteful species have to be sacrificed to 
inexperience, it follows mathematically that there would be a 
great gain in one distasteful species resembling another which 
exceeded it in numbers. If therefore, in the case of Huplea 
Distant and EL. Bremert, we accept My. Distant’s position, and 
with him “ adopt the explanation of mimicry for the resem. - 
* Ann. & Mag. Nat. Hist., Feb. 1878, p. 167. 
