IV. SCENT-ORGANS ON LEGS OE LEPIDOPTERA 629 
tibiae, but in this case it is the front tibiae which present this male 
distinctive character. 1 
In the family of the Geometridae , a beautiful and instructive instance 
of these scent-tufts, borne by the posterior legs, is yielded by Pantherodes 
pardalaria, Htibn., an insect which seems to inhabit the whole of Brazil, 
from the Equator to the Tropic of Capricorn. Spix and Martius took it 
on the Rio Negro, 2 also, at least in certain years, very frequently in the 
Province of Santa Catharina. This species also has the tibiae of the third 
pair of legs much larger in the males (PI. C, Figs. 2 and 4), than in the 
females (Fig. 1), but they do not attain extraordinary dimensions. The 
inner surface is grooved by a longitudinal furrow (Fig. 3 b) in which 
is hidden a tuft of long and fine hair, springing from the base of 
the tibia (Fig. 3 a). The diameter of these hairs is from 0*004 to 
0*01 mm., and their length equal to that of the tibia itself. The 
colour of the tuft varies in different individuals ; some of the hairs are 
a bright bay, others varying from dark grey to nearly black, sometimes 
one colour, sometimes the other predominating. Along the margins of 
the groove are scales (PI. C, Fig. 9), distinguished from those which cover 
the rest of the tibia (Fig. 8), by their much greater size, as well as by 
their shape and colour. Some of them at times reach a length of nearly 
0*001 mm., and rarely a third as long again: some are asymmetrical, with 
the shape of the crescent moon, others symmetrical, with parallel sides 
and three or sometimes two teeth at the apex. Finally, these larger scales 
on the margins.of the groove are pale straw-coloured ; the smaller ones 
on the rest of the tibia being of a lighter or darker grey. Bending over 
the edge of the groove, these large scales form a kind of tent (PL C, Fig. 6 
c and d), those on the lower margin being partly covered by those on the 
upper. There is thus produced by different means, but with equal 
efficiency, a covering which prevents the loss of any aroma which the tuft 
may contain. When the tibia is extended, the tuft begins to rise from 
its concealment, and erect itself, spreading out its hairs on all sides, but 
without exhaling any scent perceptible to the human nose, or at least not 
to mine. 
Without doubt in the vast group of the moths, of which up to the 
present only a quite insignificant number has been examined, there must 
exist numerous other cases in which a scent apparatus is borne by the egs, 
the wings and other parts of the body. The object of these lines is simply 
to assist towards the complete elucidation of the subject with which they 
deal, and to point out to the young naturalists of Brazil a vast field, as 
yet unexplored, and promising a harvest of new and interesting facts. 
1 “ Tibia enlarged and furnished with a tuft of erectile hairs.” Chenu, Encyclop. 
d’Hist. Nat., Papillons, II., p. 215.—F.M. [Sir George Hampson informs me that 
Herminia belongs to the Noctuidae, sub-family Hypeninae. —E.B.P.] 
2 Perty, Delectus Animalium Articulatorum , 1830, p. 163; PI. XXXII., Fig. 11. 
Perty here calls it Phalaena jperspicillum. —F.M. 
