SEASONAL CHANGES IN THE COMMON SQUIRREL. 403 



probably be found to occur in many other species, when equally 

 detailed observations have been made on them. 



To justify the above conclusions, the different parts of the 

 body may best be considered separately, taking the most obvious 

 first. 



T. Tail-hairs. 



In August and September there become visible on the tail, 

 among and gradually displacing the ragged white hairs of the 

 summer, a handsome set of long shining blackish-brown hairs, 

 which have hardly attained their full length before they begin to 

 lose their colour, fading gradually during the winter through 

 various shades of brown, pale brown, dull yellowish brown, straw 

 colour, and finally, by June, July, and August of the following 

 year, becoming nearly or quite white.* Then in their turn they 

 are displaced, in September, by the new blackish hairs of the 

 succeeding coat.f 



Although, as just stated, the long hairs only become visible 

 on the shedding of the old ones in August and September, their 

 extreme tips protrude from the skin much earlier, and may 

 be occasionally found in July skins, forming a short blackish 

 covering to the tail among the roots of the long white hairs of 

 the previous year's coat. 



In an intermediate condition, well represented by a skin 

 dated Aug. 19th, the tail may be more or less piebald, with the 

 middle third of its breadth black, fringed on each side with the 

 ragged white hairs of the old coat. 



f It will be observed that red is a colour not mentioned in the descrip- 

 tion of the tail, and it is a curious fact that as yet I have not seen a single 

 adult red-tailed British Squirrel. Should any readers of 'The Zoologist' 

 come across such specimens, which most people vaguely suppose to be in a 

 majority, they are requested to send them in the flesh to the writer at the 

 Natural History Museum. Mere reports of red-tailed Squirrels seen wild 

 are of little use, as, owing to the deceptive appearance presented by the red 

 flanks and constantly moving tail, many specimens seem in life to have red 

 tails which after death prove to have nothing of the sort. Young specimens, 

 however, often have red tails, and this would tend to show that, like their 

 continental relatives, the British Squirrels were formerly red-tailed when 

 adult. 



* A similar case of colour bleaching during life was described by me in 

 a Nyasa Squirrel (Sciurus mutabilis) in 1894 (P. Z. S. 1894, p. 140), not 

 knowing how much nearer home the same phenomenon might be observed. 



2 i 2 



