NORTH-CAROLINA GEOLOGICAL SURVEY. 



Fio. 39. 



epoch of these reptiles is earlier than that of the miocene 



beds. They are found in those 

 beds for the same reason that 

 the exogyra costata of the green 

 sand is also found in the mio 

 cene. &quot;While it is clear enough 

 that fossils have been washed 

 out of the green sand into the 

 miocene. I have no evidence 

 that they have been transport 

 ed into the eocene, the next 

 series above. The deposits seem 

 to have quietly succeeded the 

 green sand ; but when the mio 

 cene period arrived, there was 

 a breaking up of the older 

 series, and their contents carri 

 ed immediately up to this pe 

 riod, and under favorable cir 

 cumstances fossils of both periods were intermingled together, 

 and hence I regard the animals under consideration to have 

 lived before the miocene beds were deposited. 



The teeth which I have figured I have referred to a genus 

 of crocodilian reptiles established by Prof. Owen, and which, 

 in England, belonged to the chalk or cretaceous system. 



The following description is drawn from the teeth before 

 me : Teeth thick and conical, and slightly curved ; trans 

 verse section circular or round ; enamel traversed longitudi 

 nally by numerous transversely rugose cracks, the strongest 

 of which reach the apex ; no trenchant edges or carinae 

 proper. 



The teeth are only gently curved ; they are very strong 

 and robust, and the enamel is traversed by rather irregular 

 rugose ridges, which appear like cracks. The inside ridge is 

 stronger than the others, and are formed of two confluent 

 ones, and takes the place of a carina, and extends to the 

 point in the young tooth ; but in old and worn teeth most of 

 the ridges terminate considerably below the apex. The sur- 



