644 COLLEGE ZOOLOGY 



Order 8. Tubulidentata. AARD VARKS. One genus, 

 Orycteropus, with two species of burrowing mammals, 

 confined . to Africa. They are called Cape ant- 

 eaters. 

 Section B. PRIMATES. 1 MAMMALS WITH "NAILS." 



Order 9. Primates. LEMURS, MONKEYS, MAN. Eu- 

 THERIA with " nails "; great toe or thumb or both are 

 opposable to other digits; brain large. 

 Suborder i. LEMUROIDEA. LEMUROIDS. PRIMATES with 

 front teeth separated by a space in the middle line. 

 Example: Lemur, lemur (Fig. 528). 

 Suborder 2. ANTHROPOIDEA. MONKEYS, APES, MAN. 

 PRIMATES with front teeth in contact in middle line. 

 Examples: Cebus, capuchin; A teles, spider monkeys 

 (Fig. 530); Cynocephalus, baboon; Simla, orang-utan 

 (Fig. 532); Gorilla, gorilla (Fig. 533); Homo, man. 

 Section C. UNGULATA. HOOFED MAMMALS. 



Order 10. Artiodactyla. EVEN-TOED UNGULATES. UN- 

 GULATA with an even number of digits; the axis of 

 symmetry passes between digits three and four. Ex- 

 amples: Sus, pig; Dicotyles, peccary; Hippopotamus, 

 hippopotamus; Camelus, camel; Giraffa, giraffe; 

 Cervus, deer, etc.; Alces, moose; Bos, domestic cattle; 

 Bison, bison (Fig. 536). 



Order n. Perissodactyla. ODD-TOED UNGULATES. UN- 

 GULATA with an uneven number of digits; the axis of 

 symmetry passes through digit three. Examples: 

 Equus, horse, ass, zebra; Tapirus, tapir (Fig. 538); 

 Rhinoceros, rhinoceros (Fig. 539). 



1 The position of the PRIMATES in the midst of the mammalian series instead of 

 at the end, where they are usually placed, may seem strange to students, but man, 

 the apes, and other mammals belonging to this group retain a larger number of 

 primitive characters than do the orders that are placed above them in this classi- 

 fication. The primates excel principally in the development of the nervous system, 

 but are comparatively primitive when the bones, muscles, teeth, and other organs 

 are taken into account. 



