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ANIMAL BIOLOGY 



dactyls, or even-toed Pigs, Hippopotami, Camels, Tapirs, Sheep, 

 Deer, Giraffes, etc.; the Perissodactyls, or odd-toed Horses, 

 Tapirs, and Rhinoceroses; and the Proboscidians, or Elephants. 

 Closely related are the aquatic Sirenians, or Manatees. (Figs. 91, 

 92, 227, 238.) 



Fig. 92. — Ungulates. A, Giraffe, Giraffa camelopardalis; B, American 

 Tapir, Tapirus terrestris; C, African Rhinoceros, Rhinoceros bicornis. (From 

 Newman, after Beddard and Lydekker.) 



The Primates form the concluding legion and include Lemurs, 

 Monkeys and Apes, and Man. They are predominant chiefly by 

 virtue of their mobile, grasping hands, and their intelligence. 

 Quite appropriately Primates have been called 'the inquisitive 

 Mammals." (Figs. 93, 228, 272-274.) 



So is completed our glance at the chief types — phyla — in the 

 varied panorama of animal life from Protozoon to Mammal. 

 Necessarily brief, it is adequate for our purpose if we are impressed 

 with certain outstanding facts, not the least significant being the 

 versatility and prodigality of life. Nature has tried, as it were, one 

 experiment after another: some phyla have prospered and then 

 waned; some have gone up blind alleys and stayed there; some 

 have met the conditions of life to the full and have flourished: two 

 in outstanding fashion — Arthropods and Vertebrates. Only some, 

 then, and not all, have made a real contribution, but this has been 



