THE IRISH HARE 343 



pace is being retarded or accelerated) at two-thirds of the 

 distance from hind-foot mark to hind-foot mark measured 

 forwards. The order of the hind feet may be changed as in B ; 

 the fact that they move unevenly is visible to the eye when the 

 pace is slow, and I have seen one lifted up after the manner of 

 a terrier dog, the hare travelling for a short distance on three legs. 



I have measured a series of leaps measuring approximately 

 90, 1 46, 90, 45, 86, 42, 62, 44, 86, 47, 60 and 120 inches, the 

 average of the long and short leaps being 89 and 47 inches 

 respectively. These do not pretend to represent the extreme 

 speed of the animal, in which case much longer distances 

 would no doubt be covered. I have not noticed what Mr 

 Thompson Seton calls "spy-hops," that is, extra big leaps 

 made for purposes of observation. 



In the particular tracks figured the "triangles" of the 

 theoretical track (see p. 169) are not so evident as in the 

 tracks of rabbits figured above on p. 220. 



It is obvious that in order to leave the spoor described 

 above, the animal can only progress by alternate contractions 

 and extreme extensions of its whole body, the muscles of which 

 are thus utilised to assist those of the limbs. This method of 

 progression has been shown by Mr Edward Muybridge 2 to be 

 that of the greyhound, but the spoor of the Irish Hare indicates 

 an extreme development of the action. 



When merely wandering about at ease the length of leap 

 may decrease until the animal halts and footmarks overlap. 



The above figures may be compared with the 15-feet leaps 

 of the Brown Hare, as described in the article on that animal, 3 

 as well as with Dr R. W. Shufeldt's notes 4 on two American 

 species, of which one, the white-sided "Jack Rabbit," 5 clears 

 at ordinary times 48 inches, but if pressed, 144 to 156 inches ; 



1 The combined length of the two fore and two hind feet should be deducted in 

 order to arrive at the true length, since in each hind foot there is a space of about 

 150 mm. of leverage and variation of fulcrum, and in the fore limb, from the carpus 

 to the claws (the function of which in progression is not to be underrated) about 75 

 mm. of leverage are found, being a total of about 225 mm. for each lateral pair of 

 feet and the double of that for the action of all four feet. (See Joseph Gamgee, 

 "On the Action of the Horse," Journ. Anat. and Phys., May 1869, 375.) 



2 Descriptive Zoopraxography, 1893, 41. 3 See above, p. 287. 



4 Zoologist, 1888, 259 ; see also Editor, Field, 9th November 1895, 786. 



5 Lepus callotis callotis (Wagler). 



