The species was founded on a median and a lateral plate of 2 individuals. The clavicle is here associated with _S. scutellata_ and the interclavicle thus remains as the type specimen. There are other remains associated by Cope with _S. scutellata_ which are here shown to have closer affinities with the _S. pauciradiata_. The clavicle is a right-angled triangle, the inner and thin edge concave posteriorly, the posterior convex. The ridges and grooves are well developed on the specimen. The visceral side of the element is smooth. Cope referred to _S. scutellata_ the larger part of an individual with strongly developed ventral scutellation. This he figured on plate XXXVI, fig. 2 (123). Even a cursory glance will, however, suffice to show that the sculpturing of the clavicle just described and that exhibited by the specimen there figured are identical. Closer examination shows important differences between the species, the principal distinctions being the strongly developed ventral scutellæ in _Sauropleura scutellata_, the difference in form and sculpture of the interclavicles, and the posterior extension of the interclavicle in _S. scutellata_ which is wanting in _S. pauciradiata_. The sculpturing of the interclavicle in the form figured by Cope as _S. scutellata_, just referred to, is identical with the sculpture of the clavicles, as would be expected. The ridges on all of the pectoral elements of _S. pauciradiata_ are strong and are rather few in number, while in _S. scutellata_ the sculpturing is more in the form of interrupted grooves. The specimen (plate 14, fig. 3) exhibits the great part of the body with one fore limb. The skull is wanting. The belly was very broad and strongly protected by broad, long scutes arranged _en chevron_. The scutes are close together and form a compact ventral armor for the animal. The fore limb is very weak. The humerus is represented by its distal end only. The radius and ulna are very short and weakly developed in comparison to the size of the animal. The limbs could not have supported the animal on land and served, probably, merely as organs of equilibration, for the animal was undoubtedly aquatic. The fingers are not all preserved and there is no carpus. Numerous other remains formerly associated with _S. scutellata_ are here referred to _S. pauciradiata_, on account of the strongly developed ventral armor, which is different from that of the type of _S. scutellata_. The remains do not, however, add to our knowledge of the anatomy of the forms, as they are very fragmentary.