12 
W. Doherty — A List of the Butterflies of Engano. [No. 1, 
more and more like a palpus. Tho 8 atyridoe and Nymphalidoe are 
more developed in this respect than the Morphidce, and the Apaturidce 
much more. The Neolropidce according to Mr. Godman have the fore- 
tarsi of the female not elavate, and hence probably less developed. 
In the Danaidce and the nearest Apaturidce ( Cethosia and Cynthia), 
they attain their largest development. This can hardly be an organ 
of touch, because these feet are poorly provided with muscles, and 
are capable of but little movement. It may be an organ of hearing, 
hut it is more likely one of smell, correlated with the scent-producing 
glands of tho male. It is significant that in the Neotropidce, where 
this foot is more normal, the male has no anal tufts. 
I think the special development of this organ, which is found in 
all Tetrapod butterflies, though but little specialized in the lowest, is an 
argument for the high rank of the Danaidce. But I am aware that the 
feet of of butterflies often vary most irregularly, independently of the 
general organism. The aborted forefoot of the male shows some such 
inconsistencies, rudiments being, as Darwin has shown, eminently 
variable. Melanitis and Bletognna in the Satyridce, many Pieridce, and 
at least one genus of the Lyccenidce have the claws bifid. The number 
of joints in the forefeet of female Tetrapods also varies. And in Pseuder- 
golis, a genus of the Apaturidce, differing but little from its neighbours 
in other points, the fore-tarsi of the female, though small, are quite 
perfect, with claws, pul villus and bifid paronychia. This fact would 
place it quite outside of the Tetrapod butterflies, near the Nemeoliadce, 
if the feet offered really reliable characters. 
The prehensors of tho Danaidce are chiefly remarkable for the 
aborted uncus and the broad flat clasps. They do not vary much in the 
different species ; most in Hestia and some kinds of Danais. My notes 
are insuflicieut to permit me to generalize on the subject. It is remark- 
able that the only species in which they are really very aberrant is 
Danais aglaioides, where the clasps are prolonged downwards, and exposed 
to view even in dried specimens. This butterfly is closely allied to D. 
aglaia, differing chiefly in the shape of the wings, and they arc found 
together over much of their range. It seems likely that in this case the 
prehensors have been strongly differentiated to prevent hybridism, and 
keep the species separate.* 
* This may also be the case with the genus Lampides, where a number of pro- 
tected species, remarkably alike in colour and markings, have the prehensors extremely 
unlike, and so differently armed with hooks and pincers, that the union of different 
species would presumably bring about serious consequenoes. Great confusion has 
been caused here by the German lepidopterists, who have recently figured a great 
many species with very brief descriptions, and no account of the prohensors. The 
