PEDIGREE OF MAMMALS. 28 1 



several peculiarities of skull, they manifest the most 

 extraordinary power of adaptation to arboreal and 

 steppe-life, to land and water. The Insectivora, although 

 not nearly so rich in species, offer a similar spectacle of 

 adaptations by which their genera have become almost 

 repetitions of the Rodents ; and the Cheiroptera (bats), 

 in their most numerously represented division, may be 

 regarded as a side branch of the Insectivora, if they 

 have not proceeded directly from animals resembling 

 the Lemurid^. 



In what geological period the monkeys were evolved 

 from lemur-like forms we do not know. The few fossil 

 monkeys with which we are acquainted belong to the 

 higher families of apes, and pre-suppose a long series 

 of ancestors. The same conjecture is forced upon us 

 by the geographical isolation of the American monkeys 

 from those of the Old World, which is also combined 

 with considerable anatomical differences, although it 

 could not occur to zoologists or comparative anatomists 

 to deny their close systematic affinity. 



The relation of the lower to the higher apes requires 

 further discussion, which we shall combine with our 

 disquisition on the relation of man with the monkeys. 



