640 BIOLOGY. 



Birds on account of their wings, unto which may be 

 further added the large size of their ears. Their close 

 relation, however, with the Shrews and Rodents assigns 

 them a lower rank. They must be placed parallel with 

 the Ptilota or Flies. The dental formula of the Bats re- 

 sembles too so strikingly that of the Shrews that a rusty- 

 grown prejudice can alone place the former in the neigh- 

 bourhood of the Apes. They have obtained this post, 

 without doubt, simply because they have but two mammae, 

 and these placed upon the chest. 



The Moles cannot be removed from the Shrews. 



The choice of position now remains between the Mar- 

 supials and Rodents. And to determine this point can- 

 not prove difficult, for every one will place the former 

 above the latter on account of their size, more perfect 

 dental formula, and the hands, upon whose model the 

 hind-feet have been in many species formed. To the 

 Marsupials are annexed the Sloths, because several of 

 them still possess marsupial or pouch-bones. 



Viewed in this and in every other respect, the Rodentia 

 stand or rank the lowest ; and since the members of this 

 family are much more numerous than those of any other, 

 we may conclude that they fill up several families of the 

 asarcose animals. 



3562. The series would accordingly be as follows ; first 

 of all Rodents, then Sloths arid Marsupials ; with Moles, 

 Shrews, and Bats, all as the repetition of the Dermatozoa. 

 They are all Myoidal or Mouse-like in character. Next 

 come the Whales, Pigs, and Ruminants as the repetitions 

 of the Fishes, Reptiles, and Birds. 



The Carnivora with the Bears, Apes, and Man, as 

 being the proper representatives of the senses, conclude 

 or wind up the list. They alone have a regular dental 

 formula. We have thus 



I. Splanchno-Thricozoa ; Mice, Edentata, Marsupialia, Shrews and Bats. 



II. Sarco-Thricozoa ; Whales, Pachyderms, "Ruminants. 



III. jEsthesio-Thricozoa, Carnivora, Seals, Bears, A.pes and Man. 



3563. It is here shown, just as distinctly as in the 

 series of the classes, that no simple scale exists in the 

 history of development, and consequently in the arrange- 



