HIPPOPHAE. 



HIPPOPOTAMUS. 



HIPPO'PHAfi, a genus of Plants belonging to the natural order 

 Elaaynacea. It has dioecious flowers with ovate scaly bracts. The 

 stameniferous flowers have a perianth of two leaves adhering by their 

 points ; the stamens have four very short filaments ; the pistilliferous 

 flowers have the perigone tubular and cloven at the summit ; the style 

 is short, the stigma elongated ; the nut 1-seeded, clothed with the large 

 coloured berry-like perigone. 



The only species of this genus is the H. rhamnoides, Sea-Buckthorn, 

 which is a small shrub found on the east and south-east coasts of 

 Great Britain, and other parts of Europe. The acid berries yielded 

 by this plant are often eaten as a salad both in this country and in 

 France. This plant also yields a colouring matter, which is used for 

 dyeing yellow. Although in this country the berries are innocuous, 

 they seem to exert a deleterious influence, or are supposed to do so, 

 in some of the countries of the south of Europe. They are said to be 

 a favourite food with the Tartars, aud the fishermen of the Gulf of 

 Bothnia eat them with their fish. 



(Babington, Manual of British Botany ; Burnett, Outlinet of 

 Botany.) 



HI PPO'PODA, a genus established by Messrs. Quoy and Gaimard for 

 a marine floating Mollusk which M. De Blainville considers identical 

 with Protomedca of Ijesueur"s manuscripts, and places under his 

 (M. De B.'s) Physograda. [ACALEPH.E.] 



HIPPOPO'DIUM, a fossil genus of Conchifera Dimyaria proposed 

 by Mr. J. Sowerby in the ' Mineral Conchology of Great Britain.' It 

 includes only one British species, H. ponderotum, which is found in 

 the Lias. 



HIPPOPOTAMUS ("Imros and ITOT^'OS), the Roman name for the 

 River-Horse, and retained by modern zoologists as the generic appella- 

 tion of the animals of that Pachydermatous form. 



Dental Formula : Incisors, ; canines, ; molars, = 38. 



4 1 1 6 6 



Cuvier remarks that there is no animal that requires to be more 

 studied at different ages than the Hippopotamus, in order to acquire 

 a perfect knowledge of the molar teeth, which change their form, their 

 number, and their position ; and, in his 'Ossemens Fossiles,' he goes 

 into minute det-iil of those chan 



55' 



Teeth of Hippopotamui. (F. Cuvier.) 



In the npper jaw the first incisor is conical, straight, and a little 

 worn on its internal ride ; the second is equally conical, but curved 

 inwards. The canine tooth is short, and cut, as it were, obliquely, in 

 consequence of its abrasion against its opposite. The four molars 

 which succeed the canine are strictly false molars. The first is very 

 small, is shed as the animal advances in age, and i not reproduced 

 ii it separated by an interval from the rest of the molar teeth. These 



iearly of the same size, are also shed during the youth of the animal, 

 ire replaced by others, and the first teeth are more complicated than 

 he secoud. When these, the true and permanent molars, are worn 

 >y use, they exhibit the form of a trefoil on their crowns. The three 

 ast resemble each other generally : they are composed of four large 

 ubercles approximated in pairs, and conical before the points are 

 vorn by attrition consequent on mastication. After the first effects 



abrasion they each present, by the contour of the enamel, the- 

 i.;ure of a trefoil, or, in other words, three lobes disposed more or 

 ess regularly in the form of a triangle ; but as the abrasion proceeds 

 ,nd the tooth is farther worn down, they exhibit the form of a cross 

 with a disc in the middle. 



In the lower jaw the first incisor is long, subcylindrical, terminated 

 n a point, and a little worn on its external side. The second is of 

 the same form as the first, but much smaller. The canines are 

 oormous tusks sharpened into a somewhat chisel-like edge, the 

 >olished and abraded internal surface of which presents a shape 

 nclined to elliptical. The molars form a continuous series ; the first 

 ind the second are false molars, the first being the smallest, and 

 dropping as the animal advances in age, never to be replaced. The 

 bur succeeding teeth exhibit the same general forms as those of the 

 upper jaw. The first, which is smaller than the others, has an ante- 

 rior isolated tubercle : the succeeding teeth are nearly of the same 

 size, and have alsd an isolated tubercle, but it is posterior. 



Cuvier makes the first section of his second family of Pachyder- 

 matous Mammifers (Ordinary Pachyderms) consist of those which 

 lave four, three, or two toes ; and these he separates into two great 

 jenera, the Hippopotami and the Hogs [SuiD.fi]. The Hippopotamidtx 

 are further characterised generically as having on all their feet four 

 x>es, which are nearly equal and terminated by small hoofs (sabots), 

 an immensely massive body destitute of hair, very short legs, a belly 

 trailing against the ground, an enormous head, terminated by a large 

 tumid muzzle which incloses their great anterior teeth, a short tail, 

 and small eyes and ears. Their stomach is divided into many com- 

 partments. They live in rivers, on roots and other vegetable sub- 

 stances, and are ferocious and stupid. The genus is placed by Liunams 

 among his BMiuz, between AV/itus and Sus. Dr. J. E. jGtray brings it 

 under Eltphantidce, his third family of the fifth order, Unyulata, as a 

 genus of his sub-family Uippopotamina, and has suggested that the 

 form is allied to the Halicoridce. 



The anatomy of these creatures is in accordauce with their bulk 

 and unwieldiness. 



The skeleton of the Hippopolamidce approaches that of the Ox and 

 of the Hog ; but it presents differences which distinguish it from that 

 of any other animal. The skull, whilst in the connection of the 

 bones and the arrangement of the sutures, it bears great similitude to 

 that of the Suidte, has its own peculiarities, which render its form 

 extraordinary. 



The number of vertebrae are 7 cervical, 15 dorsal, 4 lumbar, 7 

 sacral, and 14 coccygial = 47. The atlas and the axis, besides the 

 ordinary articular facets, have each two others also towards their 

 dorsal aspect ; but taken as a whole, the cercival vertebne approach 

 nearest to those of the Hog. There is nothing very remarkable about 

 the rest of the vertebne, except that their bodies are rather flat. 

 There are 7 true and 8 false ribs of a side = 30, nearly as much arched 

 as those of the Rhinoceros, but distinguishable from them, as well as 

 from those of the Elephant, in as much as they are much wider and 

 flatter at the part nearest to the vertebra) than at the opposite end. 

 The anterior part of the sternum is compressed into a ploughshare- 

 like shape and very much prolonged into an obtuse point below the 

 first rib. The rest is depressed, and the number of pieces is seven. 

 The scapula may be easily distinguished from those of the Rhinoceros 

 and Elephant, being larger than that of the first and less than that of 

 the second, and also differing in form. In its general aspect this 

 bone reminds the observer a little of the scapula of the Hog, but 

 approaches nearer to that of the Ox in the more essential characters 

 of the spine and articulating surface. The humerus bears a singular 

 resemblance to that of the Ox ; while there is some similitude to that 

 of the Hog, which is however less in proportion towards the bottom. 

 The radius and ulna are anchylosed at an early age, leaving on the 

 outside only a rather deep furrow which occupies only three-fourths 

 of the length of the radius, and on the inside a simple aperture 

 towards the upper fourth part. These bones of the fore-arm resemble 

 those of the Ox very much, but those of the latter are more elongated, 

 and the articular facets of the lower head of the bone are, in the last- 

 named animal, less oblique. There are in the carpus points of resem- 

 blance to the Hog ; but its characters distinguish it both from that 

 quadruped and the Ox. In the metacarpus all comparison with that 

 of the Hog ceases. The pelvis is easily distinguishable from those of 

 the Elephant and Rhinoceros, from the smaller width of the ilia in 

 the Hippopotamus, and other differences. The Ox perhaps approaches 

 it more closely in these parts ; but, besides other discrepancies, the 

 lower part of the pelvis and especially the oval holes are much more 

 elongated in the Hippopotamus. The sacrum is very large, but the 

 bones of the pubis project but very little. The femur, which pos- 

 eeeaee a ligameutum tercs, is well-shaped and straight, the shaft nearly 

 equal throughout, regularly cylindrical anteriorly. The great tro- 

 clumtcr, which ia compressed laterally, dora not exceed the height of 



