82 G, F. Eaton — Characters of Pteranodon. 



Art. YIII. — The Characters of Pteranodon ; by G. F. 

 Eaton. OVitli Plates YI and YII.) 



A CAEEFUL preparation of Pterodactyl material from the 

 Niobrara Cretaceous of western Kansas has been -commenced 

 at the Yale University Museum, for the purpose of adding an 

 example of one of the gigantic species of the genus Pterano- 

 don Marsh, to the series of restorations of fossil vertebrates 

 recently attempted with success. Preparatory to this work, a 

 critical examination both of the fossils themselves and of the 

 literature based upon them has been made, and an excellent 

 opportunity has been thus afforded to extend our knowledge 

 of the skeleton of Pteranodon^ in regard to several important 

 points of structure. This, in turn, may be of great value in 

 determining the true position of the genus among the 

 Pterodactyls. 



The large collection of these reptiles made by Prof. Marsh 

 and his assistants in the held, during a period including the 

 years 1870 to 189J:, and representing, according to Prof. 

 Marsh, the fossil remains of more than six hundred individ- 

 uals, was never completely examined and described by him. 

 His series of papers upon this unique order, which appeared 

 in this Journal, 1871 to 1882, were, at the time of publication, 

 considered by him as little more than preliminary notices. 

 ]Mo detailed work on the American Pterodactyls ever issued 

 from his hands, as his attention was constantly diverted by the 

 acquisition of other and not less valuable vertebrate fossils. 



His researches both in field and in laboratory having 

 awakened the interest of the scientific world in the Kansas 

 Pterodactyls, it is not surprising to find other collectors and 

 authors engaged in similar investigations. While part of 

 Prof. Marsh's earlier work on this group was performed in a 

 somewhat hurried manner, the accuracy with which he seized 

 upon important osteological characters is amazing. In one 

 instance, at least, his opinion, after having been disputed 

 almost to the point of ridicule, proves to be much more 

 correct than that advanced by his critic. Considering his 

 great talent and the abundance of material at his command, it 

 is to be regretted that Prof. Marsh did not pursue the study 

 further before laying it aside. Had he done so, he would 

 have prevented the misconceptions which have lately gained 

 credence. 



The Sagittal Crest. 



The most important correction to the prevailing idea of 

 Pteranodon is to be made in regard to the sagittal crest. 

 Prof. Marsh in describing the skull makes use of the follow- 



