1032 THE UNGULATES, OR HOOFED MAMMALS 



severally provided with seven cheek-teeth, of which the four premolars have sub- 

 conical, pointed crowns, while the broad molar teeth carry four distinct columns, 

 which, when worn by use, show on their summits well-defined, trefoil-shaped sur- 

 faces of ivory surrounded by a rim of enamel. A peculiarity in the lower jaw of 

 the hippopotamus is the presence of a hook-like flange at its hinder extremity, as 

 shown in our figure of the skeleton. 



Summarizing the result of the foregoing description, it may be observed that 

 the hippopotami are entitled to rank as a distinct family on account of the following 

 differences from the pigs and peccaries, viz. , the broad and expanded muzzle, not 

 terminating in a disc; the subequal size of the hoofs, all of which touch the ground, 

 and the absence of flattening in the opposing surfaces of the middle pair; the 

 continually-growing incisor teeth; the complete ring of bone round the socket of 

 the eye; and the hook-like flange at the hinder extremity of the lower jaw. 



The common hippopotamus (Hippopotamus amphibius} is by far the 

 Common Hip- 

 popotamus larger of the two living species, and next to the elephant would seem 



to be the bulkiest of all existing terrestrial Mammals. A male which 

 lived for many years in the London Zoological Society's Gardens measured twelve 

 feet from the tip of the snout to the root of the tail, the length of the latter append- 

 age being twenty-two inches, and its total weight was about four tons. Sir Samuel 

 Baker states that in an old male measured by himself the length was fourteen feet 

 three inches from the snout to the end of the tail, the latter being about nine inches. 

 And the same writer estimates the weight of the hide, when freshly removed, at 

 about five hundred pounds. The height at the shoulder is some three feet eight 

 inches. This species is further characterized by having two pairs of incisor teeth in 

 each jaw, the middle lower pair being of far larger dimensions than the others. 

 The general color of the skin is a slaty-copper brown, tending more to blackish 

 brown on the back and purplish brown beneath. There is, however, considerable 

 sexual and individual variation in this respect; and the hue of the skin also varies 

 according to whether the animal has recently emerged from the water, or whether 

 it is thoroughly dry. Dr. Livingstone says that while the males are of a dark color, 

 the females are of a yellowish brown; and when hippopotami first leave the water 

 the upper parts appear brownish blue and the under parts almost flesh colored, but 

 when thoroughly dry the color of the back is blackish brown or slaty. Sir John 

 Kirk observed in East Africa nearly pure white and also spotted individuals; while 

 in others only the feet were white. In certain cases, however, a more or less dis- 

 tinct reddish, purple, or yellow tinge has been noticed. The largest recorded pair 

 of lower tusks of the hippopotamus have a total length of thirty-one and one-half 

 inches along the curve, and a basal circumference of just over nine inches. 



That the hippopotamus formerly inhabited Lower Egypt is indicated by the 

 occurrence of its remains in the mud of the delta, while this is also confirmed by 

 the frequency with which it is depicted in the ancient frescoes of that country. 

 One of these frescoes preserved in the temple of Edfu shows that the ancient Egyp- 

 tians were in the habit of harpooning these animals in much the same manner as is 

 now practiced on the upper reaches of the Nile. Teeth of the hippopotamus have 

 been dug up at Kalabsheh, a short distance above the first cataract; but at the present 



