1005.] ON THE WHITE-MANED SEROW. 329 



for the West African White-thiglied Guereza (C. vellerosus), text- 

 fig. 58, appears to exhibit a kind of retrograde development in 

 these respects. The body, for instance, has entirely lost the mantle 

 of long white hair and the tail its white " flag," while the white of 

 the perineal patch has spread on to the hinder and outer sides of 

 the thighs. In this case we find, indeed, a practical reversion to 

 the type of the Black Guereza, with the exception that the band 

 on the forehead, the sides of the face and throat, the thighs, and 

 almost the wdiole of the tail have become white, while the long 

 hair has entirely disappeared from the face. 



That the colouring and special development of the long hair in 

 the White-tailed Guereza form a protective modification, there 

 seems to be little doubt. Whether, however, the colour-phases 

 and hair-growth in the other forms are of a protective nature, or 

 are merely due to what is commonly called sexual selection, must 

 be left for those to decide who have the opportunity of seeing 

 these beautiful monkeys in their native haunts. 



2. The White-maned Serow. By R. Lydekker. 



[Received November 11, 1905.] 



(Plate VIII.*) 



In 1888 the very appropriate name of iVemorAcecZits argyrochcetes 

 was bestowed by the Rev. P6re Heude t on a large and strikingly 

 coloured species of Serow inhabiting the mountains of Central 

 China in the neighbourhood of Che-kiang in the Upper Yang-tse- 

 kiang district. Later, a fuller notice, with a figure of the skull, 

 was given by the same writer J; while in 1890 Dr. A. Henry § 

 contributed a note on skins of the species which had come under 

 his notice while in China. Hitherto, however, so far as I am 

 aware, no coloured figure of the entire animal has appeared ; 

 and since the colouring is of a very remarkable and striking type, 

 somewhat diflferent from that of the ordinary Serow, I think the 

 opportunity ought to be taken of remedying this deficiency. 



This opportunity has heen aflforded by the recent addition to 

 the Collection of the British (Natural History) Museum of a 

 mounted male specimen of this Serow and of the Tibetan Takin 

 {Budorcas taxicolor tibetana). They were acquired by Rowland 

 Ward, Ltd., from a French dealer, by whom they were stated to 

 have come from Tibet ; but I should think that Sze-chuen, or 

 thereabouts, is more probably their place of origin, unless, indeed, 

 the Serow was procured still farther east. The two are, I believe, 

 the first representatives of their respective kinds ever received in 

 England, and it is quite probable that in the case of the Serow 

 this statement may be extended to European museums in general. 



* For explanation of the Plate, see p. 331. 



t Mem. Hist. Nat. Emp. Chinois, vol. ii. p. 4, note (1888). 



I T. c. p. 228, pi. xxxi. (1890). 



§ Proc. Zool. Soc. London, 1890, p. 93. 



23* 



