FOSSIL FOOTPRINTS OF THE JURA-TRIAS. 467 



In all, forty-four genera and ninety-three species. In Charles Hitchcock's classification, 

 while the dinosaurian group was recognized, yet the carnivorous dinosaurs which may he 

 correlated with the AncMsauridae, or primitive carnivorous dinosaurs, were still retained 

 under the head of pachydactylous birds, an extremely conservative view ; while only such 

 as exhibited either manus or tail were referred to the reptihan group. 



The classification proposed in the present memoir, which will be given later, refers by 

 far the greater number of the species to the chnosaurs, though to what order some of the 

 obscure tracks belong is by no means certain ; in fact it may never be fully known. Cer- 

 tain of the truly quadrupedal forms may, with fair assurance, be referred to the Protero- 

 sauria of Seeley ' from their very dinosauroid pes, while others, so far as any evidence 

 which the tracks offer is concerned, might as readily be referred to almost any of the 

 reptilian orders. The presence of Stegocephalian Amphibia or Batrachia cannot be 

 definitely proven as yet. 



General Discussion. 



Introduction. — In the red and gray sandstones and shales of the Connecticut valley, 

 and in certain parts of New Jersey and elsewhere, have been found numerous indications 

 of the ancient beings which peopled those localities in bygone ages. These indications 

 take the form of impressions of some part of the body of these early forms, either of der- 

 mal appendages such as scutes and callosities, or of dragging portions of the body, such as 

 tlie traces made by the tail ; l)ut by far the most numerous of all are the prints of the 

 feet which render to the student a fairly complete knowledge of the size, proportions, 

 and habits of their maker and, coupled mth the knowledge gained through other sources, 

 o-ive us a considerable insight into the morphology of the feet and the affinities of the 

 forms themselves. 



Tliat both vertebrate and invertebrate creatures were here represented is certain ; 

 but, with the exception of the class Reptiha among the former, which group contains by 

 far the greater number of the tracks, it is rather difficult to assign the forms to their 

 proper classes. 



It was formerly supposed that certain parallel traces were made by the fins of fishes 

 whose remains are found somewhat abundantly in certain localities. This interpreta- 

 tion has since been doubted and the traces relegated to the group of doubtful genera. 

 Amplubians may have been present, but there are no tracks which can with absolute 

 certainty be referred to them and the same may be said of the birds though the present 



'A very primitive group related tn the Rhynchocephalia from which the dinosatirs may have arisen." (Osborn.) 



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