256 Scientific Proceedings, Royal Dublin Society. 



It is necessary to glance at the differences which Nathusius describes 

 as existing between the Hare and the Rabbit. He gives the following 

 comparison' : — 



Hare. Eakbit. 



Ulna weaker than and situated Ulna stronger than and situated 



behind the radius. beside the radius. 



Compared with the basal length of the skull and the length of the vertebral 

 column the fore and hind limbs in their entirety and in their individual parts 

 are relatively : — 



Longer in the Hare. Shorter in the Rabbit. 



Humerus loiujev than antebra- Humerus and antebrachium of 



chium. approximately equal length. 



Antebrachium shorter than tibia Antebrachium shorter than tibia 



by about one-fourth of the length of by about one-half of the length of 



the latter. the latter. 



Nathusius says elsewhere that " the humerus of the Hare is longer rela- 

 tively to the antebrachium than that of the Rabbit."^ This is just the 

 reverse of the truth ; for Nathusius' own measurements show that the 

 humerus is shorter than the antebrachium in the Hare and approximately 

 equal to it in the Rabbit.^ 



It will be of interest to compare the relations subsisting between the 

 principal bones of the limb-skeleton and between the limbs and the skull in the 

 fossil Hare from Ightbam, the recent forms of L. variabilis and in L. enropwits. 

 The investigation of tlie material before me had already been completed when 

 I received from Dr. Herluf Winge a copy of his valuable paper on the 

 mammalia of Grreenland.* In this paper he gives a table of measurements of 

 the skulls and limb-bones of a suite of specimens of L. v. glacialis (= arcticus 

 and green tandiciis of the present paper), L. variabiUs (Sweden and Norway), 

 and L. etirojjwws. I had only one imperfect skeleton of L. v. arcticus before 

 me ; and therefore the data furnished by "Winge are the more welcome. In 

 order to facilitate the comparison, the table at pp. 258-259 has been drawn 

 up; and it contains not only the results of my own measurements, but 

 similar calculations based on Winge's figures. 



' WATHtJsius, op. cit., p. 67. ■' Nathusitjs, op. cit., pp. 44, 45. 



= Hid., op. cit., p. 46. -i "Wihge, " Gronlands Pattedyr," pp. 377, 378. 



