103 



COLOUR CHANGES IN CORNISH STOATS. 



By henry CROWTHEB. F.R.M.S., Curator of the Truro Museum. 



In the Truro Museum are many types of more or less 

 lighter coloured and white vertebrate quadrupeds. I cannot 

 ascertain the precise dates of their capture, as the entry in our 

 Journal of their gift to the Museum, does not of course include 

 facts relating to the field. Most of them were given years 

 ago, and several are in a case of Cornish mammals, presented 

 by the late Mr. Clem. Jackson, of Port Loe. The animals 

 grouped in this case must have taken the best part of a 

 life-time to acquire, and include undoubted summer and winter 

 forms. It would have been interesting to know, at first hand, 

 under what conditions the country lay, when these lighter 

 coloured and white mammals were caught. 



I purpose here only to touch on the colour changes in the 

 weasel family, of which the examples on the table are members. 

 Mr. Jonathan Couch in his " Cornish Fauna " says of the weasel, 

 "it is not common for this animal to assume a pied appearance 

 in Cornwall, but it has done so in a not very cold season." In 

 the second edition of this work published by our society this 

 remark is deleted. In Bell's " British Quadrupeds," it is stated 

 that Mr. Couch has seen a white form of stoat more than once 

 in Cornwall. So far as I can learn from personal enquiries, the 

 weasel is rarely seen white in Cornwall, and we have it on the 

 authority of Mr. Bell, one of the most eminent writers on 

 British Mammals, that " sometimes, though rarely, the weasel 

 becomes white in winter."* The Rev. Mr. Jenyns in his 

 "Manual of the British Vertebrate Animals" makes of the 

 Weasel a " Var. j3. White, with a few black hairs at the extremity 

 of the tail," and of the Stoat "(Summer dressy which is the brown 

 form, 2in.d^ "{Winter dress) Wholly white, or white with a slight 

 tinge of yellow, the extremity of the tail excepted, which 

 remains black. Ohs. In spring and autumn these two liveries 

 are found intermixed." 



*History of British Quadrupeds, 2nd ed., p. 188. 



