HiNTON — The Fossil Hare of the Ossiferous Fissures of Ightham. 261 



There can be no doubt that the hare which lived in southern England 

 during late Pleistocene times was a member of the L. variahilis group. So 

 close is the affinity between this fossil form and the living L. mr. hibernicus 

 that we may regard the latter as the direct descendant of the former. The 

 fossil English Hare is distinguished from the Irish Hare by its larger size, 

 and some other characters already dealt with, which go to show that the 

 fossil form was a little less specialized than its living representative. Further, 

 the English Pleistocene Hare has no closer affinity with the fossil forms 

 described by Woldrieh and Hescheler from Zuzlawitz and Thaiingen than has 

 L. var. hibernicus with L. var. scoticus, L. var. varronis, or any of the other 

 subspecies which are recognized to-day. The fossil remains ascribed to 

 L. " diluvianus " by the older French palseontologists are too imperfectly 

 known to be drawn into the comparison ; and in any case their nearest 

 living relatives are probably to be sought among some of the continental 

 subspecies of L. variabilis, or even perhaps of L. europmis. In these circum- 

 stances it appears to be desirable to regard the English Pleistocene form of 

 L. variabilis as a distinct subspecies, for which I venture to suggest the name 

 of L. var. anglicus. 



Lepus europmus does not appear to have arrived in England until after 

 the Pleistocene period ; and it may also be that during this period, when the 

 plains of western continental Europe were inliabited by members of the 

 variabilis group, this species was absent from the north-western part of 

 Europe generally. 



According to the prevalent view the variabilis group is of boreal origin ; 

 and the extension of its range southwards is usually explained by reference to 

 the glacial phenomena of Pleistocene times, the temperature during this 

 period having been, it is supposed, so lowered as to enable the group to live 

 in the plains. With the return of temperate conditions, the Snow-Hare either 

 fled northwards or retreated to those mountain fastnesses in which we now 

 find it living. The separation of Ireland from Britain, which is supposed 

 to have happened before the passing of the cold conditions, prevented 

 L. variabilis from leaving that country when the climatic conditions were no 

 longer favourable to it; and accordingly it had to adapt itself to the 

 subsequent changes. Stated in this way the theory explains most points in 

 the geological history and geographical distribution of the group ; and conse- 

 quently we find L. variabilis figuring in geological literature as one of the 

 witnesses in favour of the former existence of extreme climatic conditions 

 in the present temperate parts of western Europe. 



The introduction of the trinomial nomenclature into zoological classifica- 

 tion, with the necessity for increased exactness of observation which its 



