248 MR. G. E. DOBSON ON SECONDARY SEXUAL [Mar. 4, 



hiding the short yellow hair already mentioned. All this yellow 

 fur, both long and short, has a clear and well-defined outline "*. 



If the shoulder-tufts, so conspicuous in the male, are absent in the 

 female of this species also, as judging from analogy we may expect, 

 we have then three species of Bats of this genus alone possessing 

 secondary sexual characters as remarkable as any known in the class 

 Mammalia. 



Temminck describes somewhat similar secondary sexual differences 

 in Pteropus macklotii. The male possesses a well-developed odo- 

 riferous gland on each side of the neck, covered by a large tuft of 

 stiff unctuous hairs of a bright chestnut colour, contrasting with 

 the surrounding fur. In the female these glands and shoulder-tufts 

 are absent. 



The same author thus describes the sexual peculiarities of Cyno- 

 nycteris stramineus, Geoff. : — " Pelage lisse, tres-court et rare ; 

 region des cotes et du devant du cou ornes d'un demi-collier roux- 

 dore a pinceaux de poils onctueux et divergens. Les teintes de ce 

 collier et des pinceaux de poils courtes et divergens qui existent 

 seulement chez le male, varient plus ou moius ; l'un des sujets a 

 toutes les parties laterales et le devaut du cou d'un teinte jaune- 

 orange encadre'e par un bande brune. 



" La femelle manque d'appareil onctueux et de poils divergens aux 

 cotes du cou ; ces parties sont d'un jaunatre terne plus ou moins 

 nuance de brun-clair. Le reste du pelage estle meme pour les deux 

 sexes "f. 



I have no opportunities here for examining specimens of Bats 

 from the western hemisphere ; and very little can be gleaned from the 

 writings of zoologists regarding the occurrence of secondary sexual 

 differences among them. However, Prof. W. Peters, who lias con- 

 tributed so very much to our knowledge of the Chiroptera, has most 

 kindly, in reply to my inquiries, supplied me with some valuable 

 information on this head. 



In the American continent and its islands the place of the Rhino- 

 lophidae or Leaf-nosed Bats of the Eastern World is taken by the 

 Phyllostomidse, which, though possessing well-developed nasal 

 appendages, are in no other respect connected with the former family, 

 but rather with the Noctilionidse, which they resemble in structure 

 and in their secondary sexual characters. 



Dr. Peters notes the presence of a gular sac, as in some species 

 of Taphozoi, in the males only of Phyllostoma hastatum and in 

 several species of Molossi, and adds : — " There is nothing more 

 striking amongst American Bats than the development of a large 

 sac in the humeral membrane of Saecopteryx, Peropteryx, Balan- 

 tiopteryx, and other genera ; and this organ is only found developed 

 in the males, the females having only a rudiment, which is so small 

 that it has been overlooked by most observers until lately." 



I have no doubt that, as the species of this little-studied order 

 become better known, as great or, perhaps, a still greater number will 



* loc. cit. p. 54. t Loc. cit. p. 85. 



