Kimeridge Clay Fauna 69 



allied Upper and Middle Jurassic genera differ from the 

 typical Plesiosaurus in the structure of the shoulder-girdle. 

 The present species is specially characterized by the moderate 

 expansion of the lower ends of the humerus and femur, to 

 which three bones are articulated. Another genus of these 

 reptiles is represented in the Ely pits by Muraenosaurus trun- 

 catus, which is typified by a vertebra from Oxfordshire 1 . 



Apparently only one type of chelonian has been recorded 

 from the Kimeridge Clay of the county. This species, which 

 belongs to a generalised Jurassic family of the group, was 

 named by Professor Seeley Enaliochelys chelonia, but without 

 sufficient description. It was subsequently identified by the 

 present writer 2 with a species from the Kimeridgian of the 

 continent, known as Thalassemys Jiugii. These Upper Jurassic 

 Chelonians had the heart-shaped shells of the modern turtles 

 (of which they were probably the ancestors), but still retained 

 claws on all the digits of the limbs. 



Fish-remains appear to be of rare occurrence in the 

 Kimeridge Clay of the county. The head of a species of the 

 genus EurycwmuSy belonging to the enamel-scaled family 

 Eugnathidae, has, however, been obtained from Ely, and is 

 preserved in the Sedgwick Museum. It has been made the 

 type of the species Eurycormus grandis by Dr A. Smith 

 Woodward 3 , and is the only specimen which fully displays the 

 character of that part of the skeleton of the genus. The 

 species is of large size. The skull and part of the trunk of 

 another enamel-scaled fish in the Sedgwick Museum, obtained 

 from the Kimeridge Clay of Cottenham, were originally de- 

 scribed as a new species under the name of Macropoma sub- 

 striolatum, but the generic title was subsequently changed 

 to Coccoderma*. That genus, although still imperfectly known, 

 is definitely included in the family Coelacanthidae. 



The vertebrate remains from the Oxford Clay of Cam- 

 bridgeshire bear no comparison in point of numbers to those - 



1 Ibid. 230. 2 Ibid. in. 148. 



3 Geol. Mag. (3) vi. 449, and Cat. Foss. Fish. Brit. Mus. in. 354. 



4 See Cat. Foss. Eept. Brit. Mus. n. 415. 



