DISTRIBUTION OF ORGANISMS. 195 



but improved in organization. Their respective parentages 

 in the bulkier families may be left for future decision. Mean- 

 while, Professor Owen's opinion may be quoted for a con- 

 nexion between the hippopotamus and peccary through the 

 medium of the Chceropotamus, an extinct animal whose 

 remains are found in South America. 



The herbivorous cetes, dugong, manatus, and walrus form 

 the basis of the great order Ruminantia, to which they are 

 allied in their gregarious habits and large bulk, as well as in 

 their food. ( 79 ) This order presents two distinct subdivisions 

 the Bovidce (aurochs, bison, buffalo, ox), leading on by such 

 intermediate forms as the ovibos or musk-ox to the sheep ; 

 and the Cervidce (elk, deer), leading on to the goat ; the 

 animals of low and alluvial grounds thus, as usual, passing 

 into smaller species adapted to more inland and elevated 

 situations. 



The last mammalian order is that which Linnaeus called 

 Primates, comprehending, however, not only the monkeys 

 and lemurs, and the Cheiroptera or bats, but the Sloths 

 (Bradypodidce), which Cuvier, merely from their want of 

 certain teeth, placed elsewhere.( 80 ) For this order there 

 remains a basis in the Delphinidce, the last and smallest 

 of the cetacean tribes. This affiliation has a special sup- 

 port in the brain of the Dolphin family, which is distinctly 

 allowed to be, in proportion to general bulk, the greatest 

 amongst mammalia, next to the oran-outang and man. 

 We learn from Tiedeman, that " each of the cerebral hemi- 

 spheres is composed, as in man and the monkey tribe, of 

 three lobes an anterior, a middle, and a posterior ;" and 

 these hemispheres " present much more numerous circumvo- 

 lutions and grooves than those of any other animal." Here 

 it might be rash to found anything upon the ancient accounts 

 of the dolphin its familiarity with man, and its helping him 

 in shipwreck and various marine disasters, although it is diffi- 

 cult to believe these stories to be altogether without some 

 basis in fact. There is no doubt, however, that the dolphin 

 evinces a predilection for human society, and charms the ma- 

 riner by the gambols which it performs beside his vessel. 

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