Zoological Society. 451 
PROCEEDINGS OF LEARNED SOCIETIES. 
ZOOLOGICAL SOCIETY. 
March 8, 1864.—D. J. E. Gray, F.RS., in the Chair. 
Description of a New Spectes or Stavrotypus (S. Savinit) 
FROM GUATEMALA. By Dr. J. E. Gray, F.R.S., erc. 
Among the interesting series of Tortoises brought by Mr. Salvin 
from Haumanchal, Guatemala, and deposited in the British Museum, 
are two specimens of a Tortoise of the genus Staurotypus, but dif- 
ferimg from the normal form of that genus in the sternum being 
narrowed and acute in front, like the sternum of Chelydra, which 
genus it resembles in having a crested though short tail. 
I would propose to divide the genus thus :— 
A. Sternum broad and truncated in front. STAUROTYPUS. 
1. Sraurorypus TRIPORCATUS, Gray, Cat. Shield Rept. B. M. 
Ajert120 b- 
Hab. Mexico (Wiegmann) ; Vera Cruz (Sallé). 
B. Sternum narrow, tapering, acute in front. STAUREMYS. 
This subgenus has the form of the sternum and the crested tail of 
Chelydra, with the sternal shields of Staurotypus. 
2. Sraurotypus (STAUREMYS) SALVINII. 
Hab. Haumanchal, Guatemala (Salvin). 
Head very large, swollen, crown covered with a thin soft skin ; 
face conical, rather produced ; nose terminal; mouth inferior; beak 
large, dentated on the edge; chin with two beards; throat warty ; 
skin of body and limbs granular ; the fore legs have several slender, 
very broad, arched, band-like shields across the inner side, the 
middle one being the broadest ; toes well developed, strong; upper 
surface covered with a single series of band-like shields, united 
to the claws by a wide, well-developed web; claws 4—5, strong, 
elongate, acute; tail short, conical, angular above, with a central 
and lateral series of tubercles, forming three short crests; the tho- 
rax oblong, covered with three short, continuous keels; marginal 
shields rather narrow, elongate ; sternum cross-like, small compared 
with the dorsal disk, narrow, slightly rounded before, acute behind, 
united to the dorsal disk by a narrow lateral process; sternal plates 
seven, thin, four pairs and a single odd one behind; the first pair 
elongate, longer than broad (probably the first two pairs of other 
Emyde united) ; the second pair broad, produced on the side, so as 
to cover the greater part of the cross-like sternum; the third pair 
elongate, narrow; the hinder plate rhombic, rather longer than 
broad, acute in front and behind; the axillary and inguinal plate 
large, covering the space between the outer lateral edge of the second 
pair of shields and the marginal plates. The front lobe of the 
sternum is very moveable at the suture between the first and second 
29% 
