OTHNIEL CHARLES MARSH 301 



the many fossil animals of North America, has afforded the best 

 support to the theory of Evolution, which has appeared within 

 the last twenty years. The general appearance of the copy which 

 you have sent me is worthy of its contents, and I can say nothing 

 stronger than this. 



"With cordial thanks, believe me, 



"Yours very sincerely, 

 "CHARLES DARWIN." 



In 1 88 1, Huxley also paid a tribute to Marsh's discovery of 

 these ancestral birds: 



"The discovery of the toothed birds of the cretaceous for- 

 mation of N. America, by Prof. Marsh, completed the series of 

 transitional forms between birds and reptiles, and removed Mr. 

 Darwin's proposition that, 'many animal forms of life have been 

 utterly lost, through which the early progenitors of birds were for- 

 merly connected with the early progenitors of the other vertebrate 

 classes,' from the region of hypothesis to that of demonstrable 

 fact." 



This notable volume on toothed birds taken in connection with 

 papers preceding and following it made Marsh easily the first 

 authority on the extinct avian class in America, and to-day most 

 of the knowledge of fossil birds in this country, from the Jurassic 

 to the Post-Pliocene, will be found in his writings. 



Western Kansas which in 1870 also furnished the first ptero- 

 dactyls found on this continent, on reexamination yielded a large 

 series of specimens pertaining to forms of unusual size, which were 

 described by Marsh in various papers from 1871 to 1884. Not 

 until 1876, however, was it found that, unlike European forms, 

 one of the distinctive features of American types of Pterosauria 

 was the absence of teeth, indicating a new group to which Marsh 

 gave the name Pteranodontia. 



Investigations on American forms of this group have recently 

 been continued at the Yale University Museum, and a forthcoming 

 memoir on Pteranodon furnishes interesting proof of Marsh's keen 

 insight and rare skill in interpreting the evidence afforded by 

 incomplete specimens. In a discussion of the skull of this flying 

 dragon, it is stated in regard to the crest: "In figuring this strange 



