202 Lull — Development of Vertebrate Paleontology. 



"To sum up my opinion respecting these footmarks, I believe 

 that they were made by animals of a prophetic type, belonging 

 to the class of reptiles, and exhibiting many synthetic charac- 

 ters. The more closely we study past creations, the more 

 impressive and significant do the synthetic types, presenting 

 features of the higher classes under the guise of the lower ones, 

 become. They hold the promise of the future. As the opening 

 overture of an opera contains all the musical elements to be 

 therein developed, so this living prelude of the creative work 

 comprises all the organic elements to be successively developed 

 in the course of time." 



Of those whose work was contemporaneous with that 

 of Hitchcock, but one, W. C. Redfield, wrote on Triassic 

 phenomena, and he concerned himself mainly with the 

 fossil fishes of that time, his first paper on this subject 

 appearing in 1837 in the Journal (34, 201), and the last 

 twenty years later. 



Paleozoic Vertebrates. — Later the vertebrates of the 

 Paleozoic began to attract attention, footprints from 

 Pennsylvania being described by Isaac Lea, beginning in 

 1849, a notice of his first paper appearing in the Journal 

 for that year (9, 124). Several papers followed on the 

 reptile Clepsysaurus. Alfred King also wrote on the 

 Carboniferous ichnites, his work slightly antedating that 

 of Lea, but being less authoritative. 



But by far the most illuminating of the mid-century 

 writers on Paleozoic vertebrates was Sir William Daw- 

 son, a very large proportion of whose numerous papers 

 relate to the Coal Measures of Nova Scotia and their 

 contained plant and animal remains. In 1853 appeared 

 Dawson's first announcement, written in collaboration 

 with Sir Charles Lyell, of the finding of the bones of 

 vertebrates within the base of an upright fossil tree trunk 

 at South Joggins. These bones were identified by Owen 

 and Wyman as pertaining to a reptilian or amphibian to 

 which the name Dendrerpeton acadianum was given. 

 Following this were several papers published in the 

 Quarterly Journal of the Geological Society, London, 

 describing more vertebrates and associated terrestrial 

 molluscs. In 1863 Dawson summarized his discoveries 

 in the Journal (36, 430-432) under the title of "Air- 

 breathers of the Coal Period,' ' a paper which was 

 expanded and published under the same title in the Cana- 

 dian Naturalist and Geologist for the same year. Daw- 

 son also printed in the same volume the first account of 



