1864.] DR. J. E. GRAY ON THE CHELYDID. 131 
mined with accuracy until the osteology of the different species has 
been compared in the different states of growth. I believe that the 
three species above named are types of distinct forms. 
3: CuEetopina, Gray, Cat. Shield Rept. 58. 
Intergular plate within the margin of the sternum. Chin not 
bearded. 
Hab. Australia. 
* Shields of disk very thin, veined. 
1. CHELODINA LoNGICOLLIs, Gray, /. ¢. 58. 
Skeleton in Mus. Coll. Surg. (no. 961). Shortly noticed by Owen 
(Cat. Osteol. Col. p. 187). 
Hab. New Holland. 
2. CHELODINA oBLONGA, Gray, J. c. 58, t. 24. 
Hab. North and West Australia. 
3. CHELODINA COLLIEI, Gray, l. c. 59. 
Hab. Swan River. 
** Shields of thorax hard, horny. 
4. CHELODINA SULCIFERA, Gray, 7. ¢. 59, t. 25, f. 2. 
Hab. Australia. 
4. Hypromepusa, Wagler; Gray, Cat. Shield Rept. 59. 
Nuchal plate long, like a vertebral, and within the margin of the 
thorax. Intergular marginal. Chin not bearded. 
Hab. Tropical America. 
1. HyDROMEDUSA MAXIMILIANI, Gray, J. ¢. 59. 
Skeleton figured in Wagler’s ‘N. S. Amph.’ t. 3. f. 2-42. 
2. HyDROMEDUSA FLAVILABRIS, Gray, 1. c. 59. 
e. The auri-occipital arch broad; skull solid; the temporal de- 
pression moderate, covered with skin, separated by a broad, 
flat, bony crown. 
5. Puatemys, Wagler; Gray, Cat. J. ¢. 53. 
Thorax depressed, light ; cavity wide. Crown of head with a con- 
tinuous skin ; temple scaly. Skull rather slight. Chin two-bearded. 
Legs with large scales. 
Hab. Tropical America. 
PLATEMYS PLANICEPS, Gray, l. c. 54. 
Skeleton figured in Wagler’s N. S. Amph. t. 4. f.1, 2, 3. 
6. Curtymys, Gray, Cat. Shield Rept. 57. 
Thorax convex, solid; cavity contracted and strengthened by two 
