FOSSIL SQUALID^ OF THE UNITED STATES. 147 



the dentine is not as compact as in C. megalodon. I have named this fine species in 

 honour of the distinguished pioneer of Tertiary Geology in the United States, Dr. 

 Samuel George Morton. 



This species appears to be rare. I have seen a single specimen in the cabinet of 

 F. S, Holmes, Esq., of Charleston, and have met with none elsewhere. 



5. C. LANciFORMis, GMes. Figs. 46, 47, 48, 49, 50, 51.— Very flat, acutely pointed, 

 triangular, nearly equilateral; the posterior edge slightly sloped, while the anterior is 

 straight. The root is not much thicker than the base of the cone, very concave, the 

 rami not symmetrical, one being much longer than the other ; in the small lateral 

 teeth this, however, is scarcely perceptible. The edges are sharp and finely 

 indented ; the inner face elevated, the outer plane, in some specimens concave. 

 Viewed laterally some are much bowed or arched forward. In the middle of the 

 outer face near the base of the enamel, is a longitudinal depression, the sides of which 

 are elevated, and unite above the horizontal middle line, and form a ridge to the apex. 

 It has lateral appendages, which are not distinct from the principal cone. The 

 enamel extends lower on the outer face than on the inner. 



I have a series of specimens from the Eocene beds of Ashley and Copper rivers. 

 South Carolina. 



6. C. suLCiDENS, Agassiz. Figs. 52, 53. — These are remarkable for their pointed 

 form and flatness and thinness. They have the form of an isosceles triangle, and 

 are about one-third deeper than long in their bodies. The inner face is a little 

 rounded, the outer is flat, appearing even concave. On the inner face near the base 

 of the enamel there is a series of plaits or folds, which causes grooves or vertical 

 furrows. The root forms a fourth, sometimes a third of the height of the tooth, it is 

 regularly concave and is recognized always by its spongy appearance. The base of 

 the enamel is nearly parallel to the base of the root, at least on the outer face. 



I have two large specimens from the Miocene of Darlington, South Carolina, one of 

 which is figured, fig. 52, and several from the Eocene of Orangeburg, South Carolina, 

 of which fig. 53 is the largest. 



Of Professor Agassiz's other species which he retains, I have not met with 

 specimens from the United States of the following : 



C. PRODUCTUS. C. LEPTODON 



C. POLYGYRUS. C. ESCHERI. 



38 



