658 



CLASSIFICATION OF MAMMALIA. 



with flat cornea. Nostrils close at 'will. All are aquatic, and 

 are Ash-eaters. Three families are recognized — 



Family. — Otariid.s. 



Species have been grouped by some zoologists into many 

 genera founded upon very slight modifications of 

 teeth and skull. The species include the Sea Lions 

 and Sea Bears, or Fur Seals. 



J. A. Allen arranged the genera and species as follows : 

 Family. — Otariid.e. 



Genera. — Otaria (Gill ex Peron), Phocarctos (Peters), 

 Eumetopias (Gill), Zalophus (Gill), Callorhinus 

 (Gray), Arctocephalus (F. Cuvier), embracing eight 

 species. 

 Family. — PhocidjE. 



Genera. — Phoca (Linn^), Histriophoca (Gill), Halichoe- 

 rus (Nilsson), Cystophcea (Nilsson), Macrorhinus 

 (F. Cuvier), Ogmorhinus (Peters), Lobodon (Gray), 

 Leptonychotes (Gill), Ommatophoca (Gray), with 

 fifteen species. 



Order.— UNGJJLAT A. 



The recent discoveries of great numbers of extinct forms, 

 more or less nearly allied, cannot be embraced under the 

 older definitions. The present term for the Order is agreed 

 upon as most satisfactory ; certainly for the present. 



These animals are all eminently fitted for terrestrial life, 

 and in the main for a vegetable diet. Though a few are 

 more or less omnivorous, none are distinctly predaceous. 

 Their toes are provided with blunt, broad nails, or in the 

 majority of cases with hoofs, more or less enclosing the 

 ungual phalanges. 



The whole group is divided into UNGULATA VERA ; 

 containing the Sub-orders Perissodactyla and Artiodac- 

 tyla, and a less well-known group of animals which are 

 called Sub-Ungulata. By far the greater number of the 

 latter group are extinct. 



Sub-order.— HYRACOIDEA. 



Family. — Hyracid.e. 



Genera. — Hyrax, Dendrohyrax. 10 or 12 species. 



Sub-order.— PBOBOSCTDEA. 



Family. — Elephantid^e. 



Genera. — Elephas, Mastodon, Dinotherium (extinct). 

 Two living species. 



Sub-order.— AMBLYPODA. 

 (Extinct forms.) 



UNGULATA VERA. 



In the typical ungulates the feet are never plantigrade, 

 and the functional toes never exceed four, the inner digit 

 being suppressed. The testes descend into a scrotum ; there 

 ia never an os penis. The uterus is bicornuate. The 

 mammae are usually few and inguinal, or may be numerous 

 and abdominal, as in Suina, but are never solely pectoral. 



Sub-order.— PERISSODACTYLA. 



Family. — Tapirid.e. 



Genera. — Tapirus, Elasmognathus. species. 



Family.— Hyracodontid^. (Extinct.) 



Family. — RhinocerontiDjE. 



Genera. — Rhinoceros. 9 species. Three families con- 

 sisting of extinct forms are naturally placed here. 

 Family. — Equidje. 



Genera. — Equus. 8 species. 



Sub-order.— ARTIODACTYLA. 



Family. — Hippopotamidte. 



Genera. — Hippopotamus. 2 species. 



Family. — Suid^e. » 



Genera. — Dycoteles, Sus, Phacochaerus, Babirusa, Pota- 

 lnochasrus. 22 species. 



Family. — Camelid^e. 



Genera. — Camelus, Avfchena. 6 species. 



Family. — Tragulid.e. 



Genera. — Tragulus, Hyomoschus. 6 species. 



The next group, called, collectively, Pecora, or true Rumi- 

 nants, forms an extremely homogeneous one — one of the 

 best defined, and most closely united of any of the Mam- 

 malia. 



Two prominent sub-groups are noticed, the Antlered and 

 the Horned Ruminants, the Cervidm and the Bovidce. 



Family. — Cervid^e. 



Genera. — Alces, Tarandus, Cervus, Dama, Capreolus, 

 Cervulus, Moschus, Hydropotes. 8 species. 



Family. — Camelopardalid^;. 



Genus. — Camelopardalis. 1 species. 



Family. — Bovid.e. 



Genera. — Bos, Bison, Bibos, Pcephagus, Bubalus, Anoa, 

 Oreas, Tragelaphus, Portax, Oryx, Addax, Hippo- 

 tragus, Gazella, Procapra, Antelope, iEpiceros 

 Saiga, Panthalops, Antilocapra, Cervicapra, Kobus, 

 Pelea, Nanotragus, Neotragus, Cephalophus, Tetra- 

 ceros, Alcephalus, Catoblepas, Budorcas, Rupicapra, 

 Nemorhedus, Aplocerus, Capra, Ovibos. 149 species. 



A group of extinct animals, combining the characters of 

 Rodents, Ungulates, and Carnivora, is placed here succeeding 

 the Ruminants. 



Order.— EODENTIA. 



Terrestrial, rarety arboreal or natatorial mammals, of small 

 size ; with plantigrade, or semi-plantigrade, generally penta- 

 dactyle, unquiculate, rarely subungulate, feet ; with clavicles 

 (sometimes imperfect or rudimentary) ; with never more 

 than two incisors in the mandible, and without canines. 



The upper incisors resemble the lower in growing uninter- 

 ruptedly from persistent pulps, and (excepting in Lago- 

 morpha), agree with them in number. The Rodents form 

 a very compact Order, readily distinguished by their large 

 chisel-shaped incisors, and by the absence of canines. They 

 include by far the greatest number of species — over nine 

 hundred — and have the widest distribution of ai y of the 

 Orders of terrestrial mammals, being, in fact, cosmopolitan. 

 Although more abundant in some parts, as in South America, 

 which may be considered their head-quarters, than in others, 

 as in Australia and Madagascar, where representatives of a 

 few genera of one family, Muridce, only are found. Thus 

 contrasting remarkably with the Insectivora, which con- 

 stitute at least half the mammalian fauna of Madagascar, 

 but are without living representatives in South Americv 



