REPTILES. 25 
external edge of the metatarsus behind the small toe. The nails are less developed than upon 
the anterior extremities, compressed at their base, acerated upon their extremity, and but 
slightly curved. 
The dorsal and lateral regions of the body and upper surface of the hind legs are covered 
with very small and irregular scales. The inferior surface of the body is plated all over with 
quadrangular scutelle, disposed upon ten longitudinal rows, the outermost of which is but 
imperfectly developed, upon the middle region of the abdomen. The second row, proceeding 
from the sides inwardly, is composed of scutelle, nearly quadrangular, whilst on the three 
remaining rows the scutellz are transversally longer, in the shape of an elongated quadrangle. 
Upon the anterior portion of the chest the series are interrupted and composed of smaller and 
irregularly-shaped scutelle. The preanal region exhibits three rather large polygonal scutellee 
surrounded by small plates, diminishing in size as they recede from the central group. 'The 
postanal region is densely covered with small plates or scales. The tail is long, subcylindrical, 
and tapering to a point. The scales which cover its surface are elongated and narrow, keeled 
upon their middle line, and disposed in verticiles or circular rows. On the upper part and 
sides of that organ the scales maintain the same width throughout their length, whilst inferi- 
orly some of them may be seen slightly tapering posteriorly. The ground-color is greenish, the 
head, the locomotory members, and the tail, marmorated with black. Two lighter stripes may 
be seen running along the sides, the uppermost starting from the surciliary ridge, the lower 
one from behind the eye across the auditive aperture, and parallel towards the posterior extremity 
of the body. Hence, along the sides of the tail toa considerable distance, the uppermost unin- 
terruptedly above the hind limbs, the lower one with a break near the origin of the thighs. 
The area enclosed by these two vitte or stripes is black, provided upon its middle region with 
a series of greenish subrounded spots. The region of the flanks beneath the lower vitta is 
either entirely black, with two or three irregular series of greenish spots, or else the green and 
the black mingle, and assume a meandric aspect. The external three series of abdominal 
scutelle are provided with a black spot upon their middle. The dorsal region enclosed between 
the uppermost vitta presents a medial, light-greenish band, edged with transverse blotches of 
black, enclosing a quadrangular space of deeper green, occasionally mottled with black. Upon 
the occiput and neck most of the space is greenish. It is not improbable that the young will 
be found to possess a more defined dorsal vitta, mayhap, similar altogether to those now to 
be observed on the sides. The inferior surface of the head, the chest, the middle region of the 
abdomen, and the preanal region, are uniformly yellowish-green. The inferior surface of the 
fore-limbs is yellowish, the inferior surface of the hind limbs and tail whitish, obsoletely 
blotched with blackish. 
Specimens of this species were collected at Chagres, isthmus of Panama, by the late Prof. 
C. B. Adams, of Amherst College, Massachusetts. 
Plate XX XVIII, fig. 1, represents the profile of Cnemidophorus preesignis, size of life. 
fig. 2, is an under view of the same specimen, showing the varied structure 
of the plates, scales, and scutell, referred to in the above description; a 
is an enlarged view of one from a femoral pore. 
. 3, exhibits the head from above. 
. 4, an enlarged toe. 
. 5, an enlarged finger. 
inn) 
ge os 09 
