Dr. J. E. Gray on new Genera of Lizards. 103 
Placosoma cordylinum is described from a specimen in the Mu- 
seum at Bonn, on the Rhine, collected by Dr. John Natterer in 
North Brazil ; and it is probable that the Holaspis Guenthert may 
also be a Tropical-American form. 
Ho.asris Guentuert, A. Smith, MS. 
Bluish brown (in spirits), with three bluish-white equidistant re- 
gular lines down each side of the head, neck, and body, and a stripe 
down the front of the fore leg. 
Hab. 2 
The specimen was purchased in Paris without any habitat affixed 
to it. 
The tail has been reproduced, and the reproduced part is of the 
normal form, fringed and toothed on the sides, but of a different (that 
is to say, uniform dull leaden) colour. 
The second genus has many characters in common with Yantusia 
of Baird, and will most probably belong to the family Yantusiide, 
as proposed in the ‘ Proceedings of the Academy of Sciences,’ Phila- 
delphia, for 1858, p. 255. 
2. PortopoGaster, A. Smith, MS. 
Head pyramidal; sides erect; crown flat, hard, bony, covered 
with very thin polygonal normal shields ; superciliary ridge bony, 
solid; temple covered with a shield ; lower jaw thick, bony, solid, 
covered with a single series of large broad, thin, membranous shields, 
which are united in a straight line on the middle of the chin ; eyes 
circular, large, lateral, without any eyelids; pupil large, circular ; 
tongue not retractile, broad, flat, attached nearly to the tip, the tip 
only obscurely nicked; teeth simple; ears oblong, large, with a 
groove to the angle of the mouth ; tympanum sunken; nostrils late- 
ral, anterior in the suture between two nasal shields, the front situ- 
ated between the upper edge of the rostral and the front odd plate. 
The sides of the neck and throat covered with round, convex 
scales of moderate and nearly uniform size. The throat with two 
folds on each side, and with a cross fold in front of the chest ; these 
folds are covered with scales of the same size and kind as the rest of 
the throat. The back of the neck, back, and sides of the body 
covered with uniform, convex, roundish scales, with numerous scat- 
tered, larger, prominent, conical, tubercular scales placed in longi- 
tudinal rows along the centre of the back, and larger and more abun- 
dant ones on the sides. The belly covered with cross series of square 
flat smooth shields, most of which have a dark large pore-like crypt in 
the middle of their hinder edge; the shields of the chest are smaller, 
more numerous, and placed in converging lines. The legs strong, 
covered with round convex scales; the hinder ones armed with 
larger prominent tubercles on the upper surface. Toes 5:5, unequal, 
slender; claws sharp, curved, the under surface covered with flat 
shields ; femoral pores large, distinct. The front of the vent covered 
with three pairs of equal flat shields, each having a very large crypt 
in the middle of its hinder edge, the hinder pair next the vent being 
the largest. The tail cylindrical, tapering, covered above with rings 
