Twelfth caudal (vert. 38): Neural arch barely complete. No spine. Thirteenth to nineteenth caudals (vert. 39-45): Similar to those of Barnegat skeleton. Twentieth caudal (vert. 46): Rudely triangular, with a peg-like posterior projection, bearing the very small posterior epiphysis. No foramina. Anterior epiphysis deeply concave in middle. _Charleston_ (female, jr.).—First caudal (vert. 28): Similar to last lumbar, but only a faint inferior median ridge. Inferior outline of centrum antero-posteriorly very concave, which is not the case in the Barnegat and Newport skeletons. Posterior chevron processes prominent. Postero-inferior oblique grooves shallow. Seventh caudal (vert. 34): Like the Newport skeleton. The transverse process not pierced or emarginate. Postero-inferior oblique grooves indistinct. Ridges on centrum very distinct. Right anterior and posterior chevron processes united and pierced by a foramen. Tenth caudal (vert. 37): Similar to the same vertebra in Newport skeleton, but neural spine very short. CHEVRONS. The number of chevrons in the North American and some other specimens is as follows: Newport, Rhode Island. 11 Barnegat City, New Jersey. 8(+3?) Charleston, South Carolina. 8+ Buenos Ayres, Argentina (Burmeister). 11 Holma, Sweden (Malm). 9 Littleton Harbor, New Zealand (Haast). 10 Warrington, New Zealand (Scott and Parker). 9 Pisa Museum (Van Beneden). 9 The chevrons are similar in form in the three North American specimens, with some differences which will be pointed out below. _Newport_ (male).—The first chevron consists of a pair of bones which are not united. They are longer than deep, their depth indeed being less than that of any one of the succeeding bones except the tenth and eleventh. Each presents one strong superior articulating facet. Second chevron, elongated antero-posteriorly, but not much deeper than the first. Third chevron very deep and only equaled in that respect by the fourth; narrowed and rounded off below. Fourth chevron largest and broadest (antero-posteriorly) of the series; expanded below and the lower border transverse. Fifth to eighth similar in form, but less deep successively, and the lower border more rounded. Ninth similar to eighth, but smaller and thinner. Tenth similar to first, longer (antero-posteriorly) than deep. Eleventh similar to tenth in form, but smaller.