part 3] A NEW PLESIOSAUR FEOM THE WEALD CLAY. '^85 



10. Desceiption of a New Plesiosaue from the Weald Clay 

 o/' Berwick (Sussex). By Charles William Andrews, 

 B.A., D.Sc, F.E.S., F.C.S. (Eead February 22nd, 1922.) 



[Plates XIV & XV.] 



The Plesiosaurian remains which form the subject of the present 

 paper were contained in a large septarian nodule from the Upper 

 Weald Clay of Berwick (Sussex). This nodule was found in the 

 excavations made by the Cuckmere Brick Company ; it was broken 

 into many fragments which were, so far as possible, collected by 

 Mr. S. Tooth, M.Inst.C.E., and by him presented to the British 

 Museum (Natural History). The pieces, many of which clearly 

 contained portions of bones, were reunited, and the gaps resulting 

 from the loss of fragments filled in with plaster of Paris, so that 

 the original form of the nodule was restored. The extremely hard 

 matrix was then slowly and with great skill chiselled away by 

 Mr. L. Parsons, who found that it enclosed a mass of bones for 

 the greater part thrown together in the utmost confusion, with the 

 result that their removal was a matter of extreme difficulty. 

 Despite these drawbacks, however, he succeeded in getting out the 

 hinder part of the skull and a nearly complete shoulder-girdle, a,ll 

 the elements of which seem to be quite undistorted by pressure, 

 a most unusual circumstance. The humeri were also found, but 

 the rest of the paddles, which probably projected beyond the limits 

 of the concretion, was lost. Numerous cervical and dorsal ver- 

 tebrae, ribs, and ventral ribs were found ; but of the pelvis and hinder 

 limb nothing remained, and only one or two imperfect caudal 

 vertebrae were preserved. 



The skull (PI. XIY, figs. 1 & 2).— This is unfortunately very 

 imperfectly preserved, the region in front of the orbits being 

 entirely lost. The posterior portion is also imperfect ; but one 

 exoccipital bone and the supra-occipital were found lying apart. 

 The palate is well preserved on the right side, as far forwards as 

 the anterior end of the sub-orbital vacuity. 



The occipital condyle (oc.c.) forms nearly a hemisphere, its 

 upper border only being somewhat flattened. Ventrally and 

 laterally it is bounded by a slight groove, but one cannot say that it 

 is pedunculate. In front of this groove the face of the bone curves 

 sharply downwards below and outwards at the sides. Ventrally it 

 terminates in the sharp posterior border of the flat platform pre- 

 sumably formed mainly by the basisphenoid, but actually covered 

 by the parasphenoid, which conceals the relations between the basi- 

 occipital and the basisphenoid. Laterally the basioccipital passes out 

 into a pair of tuberosities (tubera sphenoccipitalia) which terminate 

 in flat facets looking outwards and a little downwards. The 

 portion of the parasphenoid i^'pas) covering the basioccipital 



