THE HIPPOPOTAMUS. 



65 



elongated rectangle, somewhat contracted 



below the eyes and rounded off in front with 



a thick snout, on which the nostrils open in 



the form of S-shaped slits. The eyes are 



small and surrounded by a projecting orbit. 



The ears stand at the angles of the back part 



of the head, where it sinks abruptly down 



towards the neck, and are small and in the 



form of pointed paper-cornets. When the 



animal is in the water, its true element, it so 



to speak drives this unshapely head along 



the surface in such a manner that only the 



ears, eyes, and nostrils are visible above the 



water, which forms a small pool on the 



depressed part between the eyes and nostrils. 



The latter open in breathing with a great 



noise and can be hermetically closed in diving. 



Only when the creature leaves the water can 



we see the muzzle, on which the upper lip is 



puffed up at the sides so as to conceal the 



tusks, and this gives a peculiar curved form 



to the opening of the mouth. 



The skull of the animal is elongated in 

 consequence of the enormous size of the jaws, 

 while the brain -case is very small. The 

 dentition is terrible. In the upper jaw there 

 are two incisors, one on each side, set in the 

 two halves of the premaxilla, which are 

 separated by a wide excavation in the middle. 

 These incisors resemble short pegs, and are 

 kept sharp by use. The canines which follow 

 these incisors form two lateral projections, 

 and, like the incisors, keep growing without 

 interruption throughout life. Their crown 

 is very short, but is kept sharp by use. In 

 the lower jaws both incisors and canines like- 

 wise keep constantly growing. The inner 

 incisors are enormously long and straight, 

 and directed obliquely forwards and upwards. 

 In a young hippopotamus, whose last molars 

 had not yet cut the gum, these teeth were 

 more than a foot in length and about an inch 

 and a half in thickness. The outer pair of 

 lower incisors are smaller, but also of cylin- 

 drical form. The lower canines are of enor- 

 mous size, and curved upwards, grooved on 



their enamelled surface and worn away on 

 their inner face so as to present a sharp 

 cutting edge at the end. A pretty wide 

 interval separates the cheek- and front-teeth 

 in both jaws. In each half of each jaw there 

 are seven cheek-teeth in all — four premolars 

 with a conical elevation in the middle, and 

 three true molars, which, before they are 

 much worn, exhibit four folded conical 

 tubercles separated by two deep fissures 

 forming a cross. Through the effect of use 

 the crowns come to present to view in place 

 of the tubercles four figures like clover-leaves 

 surrounded by stripes of enamel. This figure 

 is characteristic of the teeth of adult hippo- 

 potamuses. 



The "behemoth" of the Bible is an essen- 

 tially herbivorous and aquatic animal. For- 

 merly extending from the mouths of the Nile 

 to the rivers of the Cape, it has now been 

 pushed back into the interior by the advance 

 of civilization, and in proportion as the rifle 

 shooting heavy bullets with great power of 

 penetration advances up the rivers and lakes 

 of Central Africa will this huge animal 

 gradually disappear. The natives hunt it 

 successfully by hurling against it harpoons 

 attached to floats, and then killing it with 

 lances after terrible battles. But these are 

 always only isolated encounters which cannot 

 seriously diminish the numbers of the herds. 



The hippopotamus is on the whole a 



nocturnal animal, and where it has made 



acquaintance with firearms leaves the water 



only by night, or if by day, only to bask in 



the sun on sand-banks and islands out of 



range of bullets. In the rivers and lakes 



whose banks are occupied by tasty plants 



rich in starch, such as it can easily uproot by 



means of its incisors and canines, it remains 



constantly in the water while seeking its food ; 



but, on the other hand, where the banks are 



naked it quits the water in order to browse in 



the neighbouring woods and plantations, which 



it devastates in a piteous manner. Besides 



the fact of its having tolerably palatable flesh, 



11 



Vol. II. 



