170 SATJROPTEKYGIA. 



44598. Six associated centra of caudal vertebrae provisionally 

 referred to this form ; from the Kimeridge Clay of Swindon, 

 Wiltshire. These specimens comprise one anterior centrum 

 of which the dimensions are : — length 0,043 (1*7 inches), 

 height 0,070 (2-75 inches), width 0,074 (2-93 inches); 

 then there is an interval, after which we come to three 

 anterior caudals in sequence: then another interval, 

 followed by two middle caudals, the dimensions of the 

 larger being, length 0,044 (1*75 inches), height 0,053 

 (2-08 inches), width 0,054 (2-15 inches). The anterior 

 ones have no distinct chevron-facets, but these are strongly 

 marked in the later centra. These specimens closely 

 resemble the caudals of T. cramptoni, and are totally 

 different from those of the Kimeridgian species of Cimolio- 

 saurus. Presented by the Directors of the Swindon 



Brick and Tile Company, 1 873. 



Thaumatosaurus propinquus (Blake l ). 



Syn. Plesiosaurus propinquus, Blake 2 . 

 Plesiosaurus simpsoni, Blake 3 . 



Nearly of the dimensions of T. arcuatus, the total length of the 

 type skeleton being 15 feet. About 25 cervical vertebrae, which 

 are described by Blake 4 as being relatively longer than in that 

 species, with the neural spines more widely separated. There are 

 said to be seven bones in the carpus — 3 in the first, and 4 in the 

 distal row ; but the arrangement of the bones of the distal row in 

 Blake's figure appears to be incorrect, and the bones articulating 

 with the left humerus seem to be either two radii, or a radius and 

 a tibia. 



The type specimen is in the Museum at Whitby, and was obtained 

 from the base of the Upper Lias. 



Hah. Europe (England). 



16046. Two conjoint imperfect cervical vertebras probably belonging 

 to this species ; from the Upper Lias of Crick, Northamp- 

 tonshire. These specimens have lost the neural spines, 

 while the exposed terminal face of each is also missing. 

 They differ from the nearly equal-sized vertebras of 

 T. arcuatus, No. 2061*, by the characters of the neural 



1 In Tate and Blake's ' Yorkshire Lias,' p. 247 (1876). — Plesiosaurus. 



2 Loc. cit. 3 Ibid. Index of synonyms, p. i. — Errorim. 



4 Erroneously compared with Plesiosaurus macrocephalus, see note, p. 167. 



