INSECT VARIETY. 51 



which distinguish the wings of many o£ the brilhant exotic 

 male butterflies. And in a general way this assumption is by 

 no means improbable ; for although instances occur where these 

 insignia appear in the opposite sex in measure, and, as evolu- 

 tionists would state it, acquired by the males, they have been trans- 

 mitted in the lapse of time to their consorts, yet otherwise, in a 

 majority of cases, they seem truly masculine. In the Papilionidse, 

 for instance, the front wings of the males have sometimes an 

 oval chalky spot on their under side, opposite to which there is 

 a dark brownish spot on the upper side of the hind wings, both 

 spots emitting a strong disagreeable odour. At other times, the 

 scent spot on the fore wings is replaced by a brush of hair, and 

 that on the hind wing is chalky and fragrant of musk, as may 

 be seen in the common canary-coloured butterflies of the tropics, 

 Callidryas. Here likewise the females show on either side of 

 their anal organs a shining spot odoriferous of a volatile acid. 

 A third example we may find in the male of our English 

 Clouded Yellows, where the chalky spot is seen without the 

 brush, the pot of rose-water without the sprinkler. In other 

 genera certain " plumules,''^ or club-shaped scales, fringed with 

 fine hair, have been accused of possessing scent properties. Our 

 small White Butterfly, belonging to one of these, has a male, 

 according to Kirby, redolent o£ thyme, and with some of his 

 exotic fraternity the scent is described by Dr. Miiller as 

 delicious; but in such cases a caution, as Professor Westwood 

 has noticed, is doubtless needful, for may not these bright 

 beings that bathe in sunlight and vapoury distillations the live- 

 long day, gather odour as they fly about. We have many moths, 

 likewise, with raised scales on the wing-surface, but I am not 

 aware this is the source of scent attraction. Lastly, organs of 

 perfume are said to exist in the sub- family of the Swallow Tails 

 along the anal margin of the hind wings of the males, which is 

 then recurved. They are evinced by a tuft of hair with a 

 disagreeable odour. 



In the Nymphalidae, or great gi-oup of butterflies witK rudi- 

 mentary forelegs, we find some of the common cosmopolitan 

 Dana'inse have dactylate hollow processes at the abdominal 

 extremity, which are furnished with hairs, and on protrusion 

 emit a disagreeable odour; and sexual pouches, possibly in 

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