OCR Text |
Show APPENDIX C.- RBPTILES. 363 Both of these rows meet in front of the symphysis of the jaw and behind the angle of the mouth, but leave between them a narrow area covered with very small scales. The inferior surface of the head ( fig. 8) is very uniform; the scales which cover this region are small, some subovate, others subqnadrangular. The pyramidal scales of the back constitute several irregular rows. One distinct and crowded row borders the outline of the abdomen. The scales on the belly are smooth, subquadrangular or lozenge- shaped, a little larger on the middle than toward the sides. The femoral pores are quite conspicuous ( fig. 10), from fifteen to seventeen on each side. The general hue of the specimen before us, preserved in alcohol, is olivaceous- green above, lighter below. Behind the occiput, on each side of the neck, there is an elongated patch of black, behind which a very small patch is seen, and, farther backward three or four others in pairs, triangular or quadrangular, the last of which is placed above and in advance of the hind legs. Four or five pairs of spots, diminishing gradually in size, may be followed along the tail. The dorsal patches are bordered with a line of light yellow. The abdomen appears unicolor, but, on careful examination, numerous brownish dots can be observed. The upper portion of the legs has a few small blackish spots. The specimen figured is from the valley of the Great Salt Lake, where it was collected by Captain Stansbury. PHBYNOSOMA PLATYBHINOS, Girard. PL. VII. Fio. l- S. * The general form of this species is more elongated than usual, the neck not so much contracted, and the head, consequently, more detached from the rest of the body. The shape of the head is as much a characteristic of this species as its structure. We allude to its circular form when viewed from above ( fig. 1), and to the flattening of the nose, as exhibited in the profile ( fig. 2). The upper surface exhibits two strong occipital spines, and a row of smaller ones on the temporal region, five on each side. The polygonal plates of the cordiform and flat vertex assume a symmetrica] arrangement on both sides, so as to divide the space into two ovoidal areas, the outer row of which is composed of larger plates, while those enclosed are smaller and more irregular. Thus, the |