TV. SCENT-ORGANS ON LEGS OF LEPIDOPTERA 627 
and in Rhamphidium, among nocturnal, Lepidoptera. The outline of the 
wings is also frequently modified by the presence of these scent-organs. 
Furthermore, both the organs themselves, and the sexual differences 
resulting from them are by no means restricted to the wings. In many 
species, especially among the Heterocera, they are placed in the abdomen ; 
while in some others they are developed on the legs. Inasmuch as the 
abdominal organs are, in the state of repose, almost always withdrawn 
either into the interior of, or among the scales of, the abdomen, they have 
entirely escaped the attention of entomologists. In fact, the only notice 
I have come across refers to the genus Lycorea , the males of which, as 
Doubleday states, 1 “ have a large tuft of hair on each side of the last 
segment, capable of being withdrawn to a great extent into the interior 
of the abdomen.” Like the Lycoreas and Itunas, the males also of 
Danais , Morpho , Glaucopidae , 2 Cryptolechia, and various other nocturnal 
Lepidoptera, possess scent-organs situated at the extremity of the abdomen, 
sometimes taking the form of tufts, sometimes of mammiliform or digiti- 
form protuberances, or filiform tubes of considerable length, and exhaling 
in nearly all cases a strong scent. It is rarest for these organs to be 
placed on the dorsum, as in Didonis biblis, or ventrally, as occurs in the 
Sphingidae. While in many cases these scent-organs were well known, 
but their functions undiscovered, it is different with the Sphingidae. In 
this group it has been known, for some years, that the males of certain 
species exhale a strong scent of musk, but no one has been able to find the 
spot from whence the scent emanates. It emanates from two tufts situated 
at the base of the abdomen, which are capable of retraction into a kind of 
groove formed by the scales of the first two segments. 
Finally, as to the tufts and analogous appendages which occur on the 
legs of certain Lepidoptera, but in the males only, no one has, so far 
as I know, up till now, discovered any function for them to fulfil. In 
diurnal Lepidoptera such organs seemed to be confined to the Hesperidae , 
among which two different forms of them are to be found. According to 
Westwood, 3 the male of one species from Java, Ismene oedipodea , Swains, 
has the tibiae of the third pair of legs of extraordinary size, and covered 
with dense hairs : in various other species of the family, these same tibiae 
are, in the male, furnished with a long tuft of hair. These tibial tufts 
have been utilized by Herrich-Schaeffer and other authors to characterize 
certain genera of the Hesperidae , as Achlyodes , Antigonus , etc. When one 
sees in a Hesperid, shown, by the characters indicated by Herrich-Schaeffer, 
to belong to the genus Antigonus , that the tibial tufts can be retracted 
1 Doubleday, Westwood and Hewitson, Genera of Diurnal Lepidoptera, p. 196. 
Bundles of hair, like those mentioned in the text, are shown in the figure of 
Ituna phenarete (PI. XVI., Fig. I). I have also seen them in the males of Ituna 
ilione. —F.M. 
2 See note 2 on p. 618.—E.B.P. 
3 Douhleday, Westwood and Hewitson, loc. cit ., p. 574.—-F.Mn 
