2924 Transactions. 
simple, the organ is only one-quarter the length. The same sexual difference 
in antennae and strigil occurs in Xanthorhoe, Notoreas, and Selidosema, 
but in Dasyuris, where the antennae are simple in both sexes, there is 
practically no difference in the size or condition of the strigil. In Declana 
most of the species have strongly pectinated antennae in the male and less 
strongly pectinated or simple antennae in the female. Figures of the tibiae - 
in both sexes of Declana junctilinea Walk. under equal magnification are 
given, in order to show not only the difference in size, but the strong bend 
or angle of the apical portion in the male (figs. 31, 32). 
URANIOIDEA. 
URANIIDAE. 
_ The striking day-flying North Australian moth Nyctalemon orontes 
Linn., so like a butterfly superficially, has a strigil resembling that of Papilio, 
but less folded and shorter in proportion. 
PAPILIONOIDEA. 
In the butterflies many of the families have more or less reduced anterior 
legs, and in such families the strigil has disappeared. In those families 
in which the forelegs are normally developed, however, a strigil is present. 
It is usually rather long and narrow, folded completely round, and partially 
fused (fig. 33). In the Hesperidae the strigil is almost hidden in a tuft of 
hair-scales. It is folded almost into a tube, though the edges are not fused. 
It lies strongly convex to the limb, and if viewed from the right angle an 
aperture may be observed between the two, with the hair on both surfaces — 
directed towards the middle line (fig. 34). 
which may be summarized as follows: In the Lepidoptera, with com- 
paratively few exceptions, a strigil or comb for cleaning the antennae 1$ 
found on the anterior tibiae. This strigil is a modified spur which has 
specialized forms this flat leaf-like organ has been completely folded round, 
the margins meeting and becoming fused so as again to take the form of 
a hollow spur. In one group, the Hepialidae, the strigil does not seem to 
have been derived from a spur, but to have originated as an outgrowth 
of the tibial wall. Almost invariably the development of the strigil 18 
found to be correlated with the condition and armature of the antennae, 
whether such condition be sexual or systematic. 
‚ 1 desire to express my thanks to Dr. R. J. Tillyard, Chief of the 
Biological Department, Cawthron Institute, for reading the text, and for 
much encouragement and advice during the carrying-out of the investigation > 
also to Mr. W. C. Davies, Curator of the Institute, for the excellent 
photographic plate. 
