130 DR. J. E. GRAY ON THE CHELYDID2. { Mar. &, 
Fig.l. 
Skull of Hydraspis raniceps. 
** Head moderate; crown subshielded. RutNEMYS. 
2. Hypraspis Gipsa, Gray, /.c.55; Dum. et Bib. Erp. Gén. 
t020 8h zs 
HI. nasuta, Gray, l. c. 55. 
*** Head moderate ; occipital and superciliary shields enlarged. 
Phrynops. 
3. HypraspPis GEOFFROYANA, Gray, J. ¢. 57. 
Phrynops geoffroyana, Wagler, N. S. Amph. t. 5. f. 47-51. 
The species of this genus are very imperfectly known, owing to 
the want of more specimens of the animals in different states of 
growth, some having been established from adult, but the chief from 
only young examples. Iam convinced that they cannot be deter- 
_ n 
ty 
