1908.] Records of the Indian Museum. - 103 



as a Ph/eboto)iiiis do not agree with vSchiner's ' and with Eaton's 

 definition of the genus, while the "moth fl}^" described by Captain 

 FrankUn •' appears, so far as it is possible to sa}^ to belong to a 

 very different genus probably allied to Pericoma. 



Note on the Scai.es, Bristi^es, etc. 



The scales are all very minute ; two kinds can be distinguished. 

 Those on the antennae, palpi, halteres, extreme base of the wings 

 and the femora have a colourless, more or less cylindrical, short base, 

 and a flattened^ more or less expanded blade of much greater length 

 in which a grey pigment appears to be suffused. The}" are solid 

 but bear on the surface a number of ver}- minute longitudinal 

 striations. They vary considerabh" in breadth and in longitudin-al 

 curvature, but are always thin and spatulate and are never bent at 

 anything approaching an angle. The scales on the tibiae and tarsi, 

 on the other hand, are colourless and are bent near their middle 

 in such a way that the two halves form or nearly form an angle 

 with one another. Moreover, these scales contain numerous verj' 

 fine longitudinal tubules full of air, which produce the silvery ap- 

 pearance of the parts they clothe. Both kinds of scale are usually 

 more or less imbricate, but those on the palpi are scattered, 

 while those on the second joint of the antennae alternate with 

 bristles situated nearer the base of the segment. Those on the 

 femora, halteres and third joint of the antenna lie nearly flat, 

 while those on the palpi and antennae slope outwards or upwards, 

 and are curved inwards in different degrees. The peculiar scales 

 on the tibiae and tarsi are arranged more or less distinctly in 

 annular series separated by circles of stiff hairs, this arrangement 

 being most distinct on the distal joints of the tarsi. 



The " flattened bristles " to which constant reference has 

 been made, resemble scales in several particulars when examined 

 minutely but appear on examination with a lens or a low power of 

 the microscope so like ordinary ]:)ristles that we have described 

 them as such; it is difficult to draw any exact line between them and 

 ordinary hairs. The}^ have, however, like the scales, a short, more 

 or less cyhndrical colourless l^asal portion, but the distal portion is 

 very long and only slightly flattened, always remaining relatively 

 narrow but varying considerably in this respect. Like the blade 

 of the scales of one type this flattened portion of the bristle ap- 

 parently contains a dark pigment, but it is frequently, if not always, 

 hollow and filled with air. Such bristles vary greatly in length 

 and in degree of curvature. They are longest and stoutest on 

 the thorax, to which they give an untidy, " unbrushed " appear- 

 ance owing to the fact that they stand up and slope in different 

 directions, always being more or less bent. Their sockets are 



1 Fauna Austriaca, ii, p. 630 {1864). 



2 Ent. Mon. Mag., xl, p. 55 (1904). 



3 Tnd. Med. Gazette, xli, p. 350, fig. 4 (1906). 



