LEPORID^E 165 



the skull so as to enclose foramina, or their inner borders may 

 coalesce along their whole length. The growth is gradual, 

 and forms no exact indication of the moment when the animal 

 becomes adult. But it will be found that not only does the 

 process grow towards the skull, but the spot at which it will 

 fuse with the frontal bone prepares itself as it were by roughen- 

 ing and then forming a knob. The roughening of the future 

 point of fusion for the posterior process will be found, as Miller 

 informs me, to be a reliable indication of maturity. 



Sex characters: — Males, sometimes even when quite small, 

 have distinctly thicker and shorter heads than females, their 

 ears often seem to the eye shorter and thicker, and, when of full 

 size, torn from fighting. The head of the female, whether 

 viewed from in front or from the side, is built on distinctly finer 

 lines, so that the sex of an individual can usually be ascertained 

 from a sflance at the head. 



The demeanour of a male, restless, excitable, quarrelsome, 

 sniffing the ground, and never the leader of a party, frequently 

 betrays his sex. 



Weight: — In hares old females are often heavier than the 

 heaviest males, but most observers find these relations reversed 

 in the Rabbit, but in any species an emasculated male would no 

 doubt reach a weight greater than that of any female ; the 

 average weight for a series of either sex is sometimes approxi- 

 mately equal, and might be absolutely so if the influence of a 

 sometimes perpetual breeding-season could be discounted. 



Distribution: — In contrast to bats, which decrease in number 

 of species from the continent of Europe, westwards to Ireland, 

 the British Islands, taken as a whole (but not any of the 

 three kingdoms individually) are richer in species of Leporidcs 

 than any of the neighbouring countries of Europe. This is due 

 to the possession by Ireland of a peculiar species in the Irish 

 Hare, as well as to the fact that in Great Britain the ranges of 

 the Brown and Blue Hares meet and overlap. The latter posi- 

 tion is now repeated in Skandinavia, owing to the introduction 

 by sportsmen of the Brown Hare, but it is not a natural 

 condition elsewhere in western Europe. 



Of the four British species, one only, the Rabbit, is found in 

 all three kingdoms, but its presence is everywhere due to intro- 



