Description of a New Plesiosaur. 317 



zygapophyses are relatively large ; the neural spines are incomplete 

 in all the anterior cervicals. In the posterior cervicals (text-Fig. 2) 

 the hypapophysial ridge is broadly rounded, and is best marked in 

 the anterior part of the centrum ; the ventral nutritive foramina are 

 here separated by an interval of about 1*5 cm. It is possible that 

 some of the posterior cervical ribs were still free. In this region 

 the zygapophyses are large and the anterior ones project strongly 

 forwards. The neural spines, which are not very high, slope back- 

 wards ; their anterior border is convex, the posterior concave. In 

 the hindermost cervicals the rib-facet passes up on to the arch, but 

 the condition of the specimen makes it difficult to determine in 

 which the passage actually takes place ; probably the tenth and 

 eleventh of the series as preserved may be regarded as the 

 transitional (pectoral) vertebrae. 



The dorsals (text-Figs. 3&, SB) have the centra relatively shorter 

 than the cervicals and at the same time rounder, the transverse 

 diameter being little greater than the vertical. The ventral surface 

 of the centrum is almost evenly rounded from side to side, there 

 being only a slight trace of a hypapophysial ridge, on either side of 

 which are the nutritive foramina (n.f .]. The upper part of the sides 

 of the vertebras is concave in all directions ; the lower border of the 

 concavity approximately marks the line of the suture between the 

 centrum and the arch ; at its lower angle there is a vascular foramen 

 (n.f.). The articular ends of the centrum are nearly circular except 

 for the presence of a slight depression beneath the neural canal ; 

 they are fairly deeply concave but without the sharp central depres- 

 sion seen in the cervicals ; their outer edges are sharp and well 

 defined. The neural arches are lower than in the cervical region 

 and the zygapophyses are proportionately smaller; the anterior 

 .zygapophyses (a.z.) project considerably forwards, the whole of 

 their articular surface lying in front of the centrum. A strong ridge 

 runs from the anterior zygapophysis to the anterior border of the 

 transverse process, which in the anterior dorsals is situated low 

 down on the arch but passes upwards as the series is followed back ; 

 it is compressed from above downwards. The height of the neural 

 spines (n.sp.) in the dorsal region is not known, ail having been 

 broken off short. 



Of the" limbs (text-Fig. 4) there remain portions of two paddles, 

 which I regard as posterior. One consists of the much-shattered 

 and imperfect distal portion of the femur with the tibia and fibula 

 attached. The other is the upper part of the shaft of the other 

 femur and the detached tibia and fibula, in excellent preservation, 



