580 
PLATE LVILI. 
Fics. 1-7. Psammopus RuGosus, Agass., 2 6 6 . : : 
Fic. 1. A group of three or four teeth disturbed and somewhat fragmentary. 
Mountain Limestone, Bristol, : c Ex. coll. Bristol Museum; 
Fic. 2. A thick specimen of lateral row of teeth. 
Fig. 3. Triangular tooth probably occupying the anterior extremity of line of lateral teeth 
(see woodcut on page 462). 
» 34a. Posterior extremity of same in section. 
Fries. 4, 5. Examples of ordinary form, much worn. 
», 9a. Lateral elevation of figure 5, base and crown very thin. 
Fic. 6. A large example peculiarly long in proportion to the breadth, 
Fie. 7. Upper surface of a lateral specimen. 
» 7a. Under surface of the same tooth. 
Specimens represented by figures 2-7, from Mountain Limestone of Armagh, 
Lex coll. Fnniskillen Collection. 
Page 
459 
