260 



ON THE SO-CALLED COLOUR PHASES OF THE RUFOUS 

 HORSESHOE-BAT OF INDIA {REimLOPHUS 



ROUXI, Temm.). 



BY 



Knud Andersen, f.z.s. • 



(With Plates I and 11.) 



It has long been known to Mammalogists that certain species of 

 Bhinolophus, Oriental as well as Ethiopian, show an extraordinaiy 

 variability in the colour of the fur. The extremes of these colour 

 types, or " phases " as they have been called, are often so strikingl}^ 

 different, the one being dull mouse-brown, the other brilliantly 

 orange-chrome without a trace of brown anywhere in the pelage, 

 that one can hardly be surprised that they have in some cases been 

 described as different species.* Such extremes are often repre- 

 sented among specimens from the same locality, and if the series 

 obtained is large enough it will often show several intermediate 

 " phases." No wonder that as soon as it was realized that all this 

 was merely " individual variation," some authors refused altogether 

 to consider the colour of the fur a character of taxonomic value in 

 bats. 



Rliinoloiihus is by no means the only genus showing colour vari- 

 eties of this kind. More or less similar phases occur in many 

 species of the allied genus Ili'piJOsideTos (e.g. in the commersoni, 

 hicolor, speoris, galeriius and caffer groups) ; further in Asellia, 

 Trioeno'ps and Rhinonycteris, all of which are closelj' allied to Hippo- 

 sideros ; again in Nyct<irit>, and in some Phyllostomatidue, Emhallo- 

 nuridce, Molossidce, and Vesp)ertilionidai . They may be found to 

 exist also in other families of Chiroptera, — in any case it is evident 

 that their occurrence is a rather common phenomenon in bats. 



Hitherto nothing has been known of these phases beyond the 

 mere fact of their existence. Whether they are seasonal, or 

 whether the individual moults " true " to its phase during the 

 whole of its lifetime, are questions which, so far as I am aware, no- 

 body has attempted to answer. The scarcity of large, carefull}^ 

 dated and sexed series of skins sufficiently explains why nobody has 

 felt tempted to attack the problem. 



Owing to the fine work recently done by the collectors for the 

 Bomba}^ Natural History Society's Mammal Survey of India this 

 scarcity of material no longer exists so far as certain Indian species 

 of Rhinoloplius and Hippiosideros are concerned. And it happens 



• The Rufous Horseshoe-bat of India is a case in point. Kelaart's Bhinolophtis 

 cinerasccns ('Prodromus Faunie Zeylanica», ]8r>2^isthe dark, his Bh. rammanika 

 an intermediate, and his lih. rubidus the orang'e " phase " of Rh. rouxi (see 

 P. Z. S. 1905, ii, p. 99; . 



