420 Bulletin American Museum of N^atural History. [Vo]. XXVII, 



Cetacea, Carnivora and Ungulata. The larynx, according to Flower 

 (Flower and Lydekker, p. 233) resembles that of Hippopotamus. The 

 prolongation of the larynx into the posterior nares may be regarded as an 

 aquatic develo{)ment of the retrovelar larynx of Insectivores. The marked 

 aquatic modifications in the petro-tympanic region are readily derivable 

 from normal Placental conditions as exemplified in the Carnivora and Ungu- 

 lata (Boenninghaus, quoted by van Kampen, 1905, p. 653). 



C 07} elusion. 



The resemblances of the Cetacea to the Suilline Artiodactyls which was 

 emphasized by Flower, may possibly be connected with the derivation of the 

 Artiodactyls from Creodonts (p. 403). Aside from the evidence (p. 410) cited 

 by Beddard for relationship with the Edentata the prevailing resemblances 

 of the Cetacea (including theZeuglodontia) seem to be with the Insectivore- 

 Creodont group, rather than with the Ungulates, Rodents, and Edentates. 

 It would not be surprising to fintl true Odontocetes in the Eocene, since so 

 many other Placental orders were already differentiated at that time, but no 

 good evidence of an especially great antiquity of the order or of relationship 

 with Marsupials or pre-Placentals has been advanced. 



The hypothesis that the resemblances between Odontocetes and Mystaco- 

 cetes are largely of a convergent character (Kiikenthal) has been cogently 

 di.sputed by Weber (1904, pp. 583-584). 



CHAPTER XI. OSTEOLOGICAL MISCELLANIES. 



The need of a netv osteologi/ of the Mammctlia. 



In preceding chapters the object has been to review and interpret evi- 

 dence bearing on the genetic interrelations of the mammalian orders. Osteo- 

 logical characters of living and fossil mammals have naturally entered largely 

 in this attempt, but attention has l)een centered on questions of phylogeny 

 rather than upon osteology itself as a method of inquiry. The present 

 chapter is designed to introduce to the student a few of the problems of 

 modern osteological research, to assist him in tracing the probable history of 

 certain parts of the skeleton in the more primitive orders, and finally to 

 express the present need for a new general treatise on the osteology of living 

 and fossil mammals. 



Recorded observations of osteological characters furnish of course the 



