HIPPOPOTAMUSES, PIGS, AND DEER 317 



it probably became one-coloured in its maturity like all the big 

 deer, though the females and young may have shown the 

 white spots. 



The megaceros in England was certainly co-existent with 

 the earliest types of man that arrived in Britain, but it dis- 

 appeared soon after their arrival, no doubt in consequence of 

 the attacks that were made on it as an article of food, but also 

 because at that time there existed in Britain enormous lions, 

 and one, if not two, forms of sabre-toothed feline. The megaceros 

 does not seem to have thriven much in Scotland, or to have 

 existed there in any great numbers. Indeed, up to the present 

 its remains have only been found in Ayr and that portion of 

 Scotland which approaches nearest to Ireland, and where the 

 last land bridge existed which connected Ireland with Great 

 Britain. Across this bridge the gigantic fallow deer travelled, 

 and found in Ireland its last home. In this almost-island, 

 separated then from England and Wales by the Irish Gulf, but 

 connected still with the south-west of Scotland by a bridge which 

 included the Isle of Man, 1 the grandest culmination of the deer 

 tribe found itself at first with no worse enemies than the wolf 

 or the bear. When Ireland became finally insulated at the close 

 of the Pleistocene period, only three causes could have brought 

 about the extermination of the megaceros: (i) It may have 

 become so over-specialised that sterility ensued. It generally 

 seems to occur in such instances as where much-specialised types 

 are cut off" by the sea and obliged to lived on an island that 

 unless they degenerate into a dwarfed form they die out from 

 increasing sterility on the part of males and females. The 

 extravagance in antler growth on the part of the males 

 of these deer may actually have reacted unfavourably on the 

 generative powers. (2) The massing of these huge deer may 

 have caused the development of some bacillus, which, like the 

 poison conveyed by the mosquito or the tse-tse fly, caused a 

 disease leading to their rapid extermination. (3) Probably the 

 last and most effective agency was the British sportsman (if I 

 1 In which locality the megaceros existed in some numbers. 



