1877.] oF j [Cope. 
BaRIissia Gray. 
Two pairs of internasals; interfrontonasals wanting; frontonasals 
present. 
Species: B. antauges Cope; B. bocourtii Pet.; B. lichenigera Wiegm.; 
B. imbricata Wiegm.; B. rudicollis Wiegm. 
An extinct genus of the family has been found in fie Miocene beds of 
the White River group of Colorado, which I have called Peltosawrus.* 
The scales in that genus were conjoined by sutural borders and not imbri- 
cate, as in the recent genera. 
PrEROGASTERUS MODESTUS, Sp. Nov. 
Scales 49 slightly convex above, but not keeled, excepting those of the 
tail, which are strongly and obtusely carinate or ribbed; an azygos 
scute between the two anterior pairs of internasals. Internasals of first 
pair reaching first labials. Internasals of third pair elongate, in contact 
with frontonasals behind, apparently including the small lateral inter- 
frontonasals. Two postnasals; a large plate, the anterior canthal, de- 
scends to the labials, from the inferior part of which a loreal may be sepa- 
rated. Preoculars two or one. Two pairs of large infralabials in contact, 
following the symphyseal, without a postmental; two pairs follow, of 
which the anterior are separated by one scute. Lateral fold extending 
from ear to vent ; the granular area extending above the humerus. Ap- 
pressed limbs separated by six cross-rows of abdominal scales, or the 
length of the fore arm. Rows of scales from nape to origin of tail, forty- 
seven ; do. from front of humerus to vent, thirty-eight. 
The tail is not very long and is grooved below as well as above. Total 
length, .150; length to meatus auditorius, .012; to vent, .072; length of 
hind leg, .019. Color above, brown; below, olivaceous. The sides are 
a reddish-brown or maroon, bordered above by a blackish line which 
separates it from the dorsal color. 
This species differs from all others of the genus in the extinction of the 
small plate which truncates the lateral angle of the interfrontonasal. As 
a consequence of this, the latter has a diamond shape, as it does not reach 
the frontal plate behind nor the azygos plate in front. The smooth scales 
also separate it from all others of the genus. 
The precise locality from which the specimens of this lizard were sent 
to the Smithsonian Institution is uncertain, but is probably Guatemala. 
GERRHONOTUS MONTICOLUS, sp. nov. 
‘*Gerrhonotus fulous Boc,’’ Cope, Journ. Ac. Phila., 1865, p. 118, nec 
Bocourtii. 
Scales keeled on the middle line of the back, to the number of three or 
four rows ; other dorsal and lateral series smooth ; those of the superior 
surface of the tail keeled strongly. Lateral fold extending from ear to 
vent; granular scales extending above the humerus. Scales above and 
* Annual Report U.S. Geol. Surv. Terrs., 1873, p. 512. 
PROC. AMER. PHILOS. soc. xvit. 100. 
