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them and lost them, when there appears to have been no real reason 

 for her to have them and no use that she could make of them, than to 

 suppose that the male has acquired them, and that, in such cases as these 

 in which the female now more or less has them, the male has trans- 

 mitted some tendency in the direction of their development to the 

 female. We can hardly leave the subject of antennae without re- 

 ferring to those of the Adelidce consisting of the genera Nemopliora, 

 Nematois and Adela. So different are they in the sexes, that early 

 authors separated them by their antennas alone as different species. 

 Dr. Chapman informs me that Incurvaria muscalella is structurally very 

 near Adela. The males of the former have pectinated antennas, those of 

 the latter long ones. It may, therefore, be supposed that the long 

 antennas of Adela are simply the result of a method of increasing the 

 antennal surface, as pectinations do in some other species. It may be a 

 new and artistic method, possibly it is an old and antiquated one. 



(2). SCENT GLANDS AND PATCHES. Having referred to the fact that 

 insects probably use their antennas as one of the sets of organs by means 

 of which the males search out the females, and that this is probably done 

 through the sense of smell, it becomes clear that there must be some 

 scent given off by the insects by means of which the opposite sex is 

 attracted. The work of Fritz Miiller has made us conversant with 

 special organs in which scent is produced (although he himself hardly 

 indicated their use in any sexual relation) and these are divided by 

 Scudder into three classes : (1). " Extensible glands on the abdo- 

 men," as are found in Anosia, in the Euplceince and Heliconince. (2). 

 " Tufts or pencils of hairs found on various parts of the body including 

 the legs and wings." Fritz Miiller found a pencil or tuft of long hairs 

 near the front margin of the hind wings of the male in the Ithyonida, 

 and although the same organs are found in the female, they are neither 

 so large nor so well-developed and the vanilla-like odour given off by 

 the male is not so strong or noticeable. In Prepona, a tuft of black hairs 

 on the hind wings gives out an odour, whilst, in one of the species 

 Thaumantes (belonging to the Morpliince), pencils of hairs called 

 " scent-fans," are situated on the upper surface of the hind wings near 

 the base. Similar tufts, giving out a jasmine-like smell, occur in a 

 species of Catopsilia, and Miiller also records a faint odour in some of 

 the higher Hesperidi, which comes from pencils of hairs found in the 

 hind tibias of the male. This brings us close to a case in our own 

 fauna in which an odour is given off from the aborted hind tibias 

 of the males of Hepialus hectus (<Ent. Kec.' &c., vol. iii., p. 

 77). (3). " Clusters of scales." These according to Scudder, appear 

 to be confined to the male sex. Nice vi lie states that Antirrhea (one of 

 the Satyrince) gives out an odour from a collection of scales on the 

 hind wings at the anterior base of the upper surface, the area being 

 covered by the fore wings, whilst Scudder gives many other examples. 

 Taken in connection with the power which certain butterflies and 

 moths possess of being attracted by the opposite sex, generally, although 

 by no means universally, the male by the female, these scent glands 

 undoubtedly show, if they do not positively tend to prove, a distinct 

 sexual use which may now be readily understood. The power of 

 " assembling " in British moths especially, is so well recognised that it 

 is almost useless to recall special instances, but I would call to mind 



