IV. JURASSIC SAURIAN REMAINS INGESTED 

 WITHIN FISH. 



By C. R. Eastman. 1 



(Plates X-XI.) 



Paleontology affords numberless instances where the nature of 

 the food-supply of various lower and higher vertebrates can be 

 positively determined by the actual stomach-contents which have 

 been preserved within the abdominal cavity of the creatures concerned. 

 These instances are sometimes of special value in confirming a priori 

 conclusions respecting the diet of fossil vertebrates based upon the 

 general character of their dentition. Other cases may attract interest 

 on account of peculiar conditions or associations, which are either to 

 be directly observed, or suggest themselves by inference. Mention 

 should be made, too, of the considerable literature which has grown 

 up within recent years concerning coprolitic matter and so-called 

 " gastroliths, " or stomach-stones. 



A few of the above-mentioned occurrences are deserving of par 

 ticular notice, on account of their possessing special points of interest, 

 and because they afford a sort of standard for estimating the impor- 

 tance of a newly discovered case of fossilization about to be described 

 in the present article. 



Among mammals, the most familiar instances of the preservation 

 of undigested food in the alimentary tract are furnished by the 

 mammoth and mastodon. A dozen years or so ago much discussion 

 was aroused concerning the possible survival into modern times and 

 domestication by man of the so-called Neomylodon listui of Ameghino, 

 or Grypotherium domesticum of Roth. Concerning the antiquity of 

 the remains that have been described under these names, the last 

 word would seem to have been spoken by Dr. A. S. Woodward in 



1 An abstract of this article was presented at the annual meeting of the Pale- 

 ontological Society, held at Washington, D. C, December 28, ion. — Editor. 



2 On a portion of a mammalian skin, named Neomylodon listai. Proc. Zool. 

 Soc, London, 1899, p. 154. Exhibition of newly discovered remains of Neomylodon 



from Patagonia. Rept. 69th Meet. Brit. Assoc. Adv. Sci., Dover, p. 783. 



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