NORTH-CAROLINA GEOLOGICAL SURVEY. 



243 



ven county. One margin is grooved the whole length, and 

 straight, the other is curved and grooved only at 

 FIG. 93. base. Figure the natural size. I have also found 

 smaller ones, which belong apparently to the same 

 species. 



FAMILY MILIOBATIDES. 



Rays whose tails are provided with serratine 



stings. 



GENUS MILIOBATIS. 



Sting dentated upon one margin. No stings of 

 this kind have as yet been met with. 



GENUS TRYGON. 



Sting with both margins dentated. 



TRYGON CAROLINENSIS. N. S. (FigS. 91 & 92.) 



Teeth in mosaic, the ends angular, they 

 being bounded by six lateral planes. 



Sting serrate, (Figs. 94 & 95,) grooved 

 longitudinally, rounded on one side. Fig. 



FIQ. 91. 



FIG. 92. 



FIG. 94. 



FIG. 95. 



95 shows the form of a tranverse section. 

 These specimens were found in the upper part of the eocene 

 marl in Craven county, and as the teeth and stings were found 

 in proximity, it is inferred that they belonged to one specie. 



CLASS GANOIDEA. FAMILY PYCNODON1TDAE. 



This family possess teeth of a cylindrical form, and which 

 are arranged upon both planes of the jaws in the form of a 

 pavement. The longer axis lies across the mouth from side 

 to side, but set in rows arranged from before backwards. The 

 middle rows contain the longest teeth, and they diminish in 

 length towards the sides of the mouth. An idea of this ar- 



