A FOSSIL SPECIMEN OF THE ALLIGATOR SNAPPER 

 (MACROCHELYS TEMMINCKII) FROM TEXAS. 



(Plates XVIII AND XIX.) 

 By OLIVER P. HAY. 

 (Received May 23, 191 1.) 



The writer has received for examination from Professor Mark 

 Francis, of the Texas Agricultural Experiment Station, at College 

 Station, Tex., a nearly complete skull of the great fresh-vvatcr tor- 

 toise known as the alligator snapper. This fine specimen was dis- 

 covered last summer or autumn during some dredging operations in 

 the Brazos River, hetwecn College Station and Navasota. After 

 passing through various hands it came into the possession of Pro- 

 fessor Francis, who, on application, kindly transmitted it to me. 

 With the skull came also a part of a carapace, which doubtless be- 

 longed to the same animal. The skull was found in a mass of 

 gravel, and had undoubtedly been washed out of the river bank 

 not far away. This proximity of the place of burial is evident from 

 the little damage done to the skull, and is made more probable from 

 the presence of a part of the shell. 



The cavities of the skull, when it came into Professor Francis' 

 hands, were full of gravel, wedged in very tightly. Some of this 

 gravel was sent with the skull. It was strongly colored with iron 

 oxide ; and this oxide served to cement the bits of gravel together 

 and to the bone. The bone is also colored with the oxide, and it 

 is so thoroughly mineralized that, on being struck, it rings like a 

 piece of porcelain. 



It would l)c interesting to know exactly the geological age of 

 this specimen ; but it appears now impossible to determine this. 

 Professor Alexander Dcussen, of the LTniversity of Texas, has been 

 engaged in studying the Quaternary and Recent deposits of some 

 of the rivers of Texas ; and a part of his results is soon to be pub- 

 lished by the ITnitcd States Geological Survey. He has kindly in- 



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