160 LEPORIDvE 



of North America and the arctic regions, and the varying hares 

 of both continents. The other, which he styled Caprolagus, 

 embraced all other forms. Later writers, however, such as 

 Lyon, Smithsonian Miscellaneous Collections, xlv., 389, 15th 

 June 1904, and Nelson, N. Amer. Fauna, No. 29, 31st August 

 1909, consider that Forsyth Major's group, Caprolagus, includes 

 several genera not less clearly defined than Lepns. Only one 

 of these, Oryctolagus, containing the rabbit, affects British 

 naturalists. 



Further subdivision of the large and unwieldy genus Lepus 

 is inevitable, but has not hitherto been successfully effected. A 

 commencement may be made with the Greenland Hare, 

 L. groenlandicus of Rhoades, which is thoroughly differ- 

 entiated from any other known form, and I propose to assign 

 it to a new genus — Boreolepus — based specially on its pro- 

 truding premaxillary region and large slightly curved upper 

 incisors which stand out clear of the skull when viewed from 

 above. These characters, together with the stout fossorial 

 claws, heavy wool-like coat and permanent white (or whitish) 

 colour, affecting both hair and underfur, form a combination 

 denoting extreme specialisation to suit very unusual conditions 

 — for the animal has to scratch and pull out its food from under 

 snow (see Manniche, Mammals of North- East Greenland, 19 10, 

 31) — and unapproached by any other known hare. 



The Greenland Hare is a remarkable instance of adaptation 

 to the intense arctic conditions in which it exists. Inhabiting 

 the permanent snowfields of the north coast of Greenland and 

 Ellesmere Land, on which it is the companion of the Northern 

 Musk Ox, Ovibos wardi, it penetrates beyond 83 north 

 latitude as far towards the Pole as terrestrial mammals can 

 exist. In spite of the rigorous climate it is a large form, 

 reaching a weight of 8 to 10 lbs. (Feilden). Although it 

 produces only one set of young in the brief arctic summer, 

 these are numerous enough to equal the combined product of 

 two or three litters of some of the southern species, for Feilden 

 (Zoologist, 1877, 354, and Appendix to Nares's Voyage to the 

 Polar Sea, 1878, ii., 204) records seven to eight young; and 

 Fabricius (Fauna Grosnlandica, 1780, 25) eight. 



There are four British species of Leporidce, the arrangement 



