72 ERINACEID^— ERINACEUS 



never — in this country — been studied in detail until Mr Moffat^ 

 undertook the task at Ballyhyland, County Wexford, Ireland. 

 His observations show that the animal is herein no less eccentric 

 than in its appearance and general habits. Watching its haunts 

 regularly throughout a single winter from 26th October to the 

 end of February, he found it abroad on fifteen nights in November, 

 nine in December, four in January, but not at all in February. 

 The hibernation, in so far as it showed a progressive decrease up 

 to February, resembles that of the Pipistrelle, but beyond that 

 point there was no coincidence. The winter appearances of the 

 bats depended entirely on temperature, and they were always 

 active when the weather was mild. On the contrary, there was 

 no evidence that warmth had any effect in waking up the 

 Hedgehog ; indeed, it was almost invariably on the cold nights 

 that it was encountered, as if its winter activity was independent 

 of weather. It is noteworthy that, although in December 

 and January bats were observed on nineteen and hedgehogs 

 on thirteen occasions, yet there were only two nights in 

 December and not one in January on which both were seen 

 abroad simultaneously. 



Mr Moffat's remarks can only be regarded as conclusive for 

 a single winter and a particular locality. It is clear that the 

 hibernatory habits of an animal having a wide geographical 

 range must vary considerably, and that for the hedgehogs 

 there will be found many variations between the routine of those 

 southern forms which, according to Blanford, never hibernate, 

 and the more northern, the hibernation of which in Germany 

 is described by Blasius as commencing, apparently irrespective 

 of date, only when the temperature drops to 3875° or 36'5° F,, 

 and terminating in March when the temperature of mid-day 

 rises to 54*5° or 59° F. 



Evidently extreme eccentricity and uncertainty are the main 

 characteristics of the hibernation of the animal in Ireland, 

 and on this point it is well to remember that Mr Moffat's notes 

 are supported by the recorded observations of other naturalists, 

 who have remarked on its discontinuity' and upon the un- 



1 Irish Naturalist, 1904, 81-87. Moffat has also sent me some MS. notes supple- 

 menting his paper. 



2 Grabham in Yorkshire, Zoologist, 1896, 76. 



