. Carnegie Institution of Washington publication. 4s FOSSIL TURTLES OF NORTH AMERICA. specimens just mentioned. The number of the specimen is 336. It presents the shell complete, the dorsal and the cervical vertebrae, the skull quite complete, the shoulder and pelvic girdles, and portions of all the limbs. The skull will he described first. When buried the skull was undoubtedly complete, but has suffered somewhat during disinterment and preparation (plate 5, tigs. 3, 4). The bone is extremely brittle and much fractured. On this account, and because of the roughness of the surface, the sutures
. Carnegie Institution of Washington publication. 4s FOSSIL TURTLES OF NORTH AMERICA. specimens just mentioned. The number of the specimen is 336. It presents the shell complete, the dorsal and the cervical vertebrae, the skull quite complete, the shoulder and pelvic girdles, and portions of all the limbs. The skull will he described first. When buried the skull was undoubtedly complete, but has suffered somewhat during disinterment and preparation (plate 5, tigs. 3, 4). The bone is extremely brittle and much fractured. On this account, and because of the roughness of the surface, the sutures are mostly undeterminable. The length from the occipital condyle to the end of the snout is 66 mm., nearly the same as that of Marsh's specimen. In form it is wedge-shaped, but not so narrow as Marsh's laterally crusht specimen. The width at the quadrates is 48 mm. The supraoccipital spine is missing. It is doubtful whether it ever had any considerable length. The parietals lack about 5 mm. of extending backward as far as the occipital condyle. The roofing of the temporal region is like that of the skull just described. Whether or not the parietals join the squamosals can not be determined; they probably do. The orbits had a diameter of 15 mm., but some allowance must be made for distortion; they appear to have been larger than those of Marsh's type. The interorbital space measures 9 mm. Apparently the sutures bounding the frontals laterally can be distinguisht, and possibly those limiting these bones anteriorly. Nasal bones can not be distin- guisht. The maxillary bone is only 3 mm. wide below the orbit. The tympanic cavity appears to have been small. The stapedial passage was open behind. The quadrates appear to have been directed slightly forward. The lateral squamosal processes extend behind the occipital condyle about 5 mm. On the upper surface there is observed on each side a groove, or sulcus, which starts about 8 mm. from the midline at the hinder border of the temporal
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