THE DESCENT OF MAN 



the male is generally brighter than that of the female."'" 

 Dr. Gray informs me that he specified the African squirrels, 

 because, from their unusually bright colors, they best exhibit 

 this difference. The female of the Mus minutus of Eussia is 

 of a paler and dirtier tint than the male. In a large number 

 of bats the fur of the male is lighter than in the female." 

 Mr. Dobson also remarks, with, respect to these animals: 

 "Differences, depending partly or entirely on the posses- 

 sion by the male of fur of a much more brilliant hue, or 

 distinguished by different markings or by the greater length 

 of certain portions, are met only, to any appreciable extent, 

 in the frugivorous bats in which the sense of sight is well 

 developed." This last remark deserves attention, as bear- 

 ing on the question whether bright colors are serviceable 

 to male animals from beiag ornamental. In one genus of 

 sloths, it is now established, as Dr. Gray states, "that the 

 males are ornamented differently from the females — ^that is 

 to say, that they have a patch of soft short hair between 

 the shoulders, which is generally of a more or less orange 

 color, and in one species pure white. The females, on the 

 contrary, are destitute of this mark." 



The terrestrial Carnivora and Insectivora rarely exhibit 

 sexual differences of any kind, including color. The ocelot 

 {Felis pardalis), however, is exceptional, for the colors of 

 the female, compared with those of the male, are "moins 

 apparentes, le fauve ^tant plus terne, le blanc moins pur, 

 les raies ay ant moins de largeur et les taches moins de di- 

 am^tre."'"' The sexes of the allied Felis mitis also differ, 

 but in a less degree; the general hues of the female being 

 rather paler than in the male, with the spots less black. 

 The marine Carnivora or seals, on the other hand, some- 



2» "Annals and Mag. of Nat. Hist.," Nov. 1867, p. 325. On the Mus 

 minutus, Desmarest, "Mammalogie," p. 304. 



" J. A. Allen, in "Balletin of Mua. Comp. Zgolog. of Cambridge, United 

 States," 1869, p. 207. Mr. Dobson on sexual characters in the Chiroptera, 

 "Proe. Zoolog. Soc," 1873, p. 241. Dr. Gray on Sloths, ibid., 1871, p. 436. 



'* Desmarest, "Mammalogie," 1820, p. 220. On Felis mitis, Rengger, 

 ibid., s. 194. 



