Sauro'pterygia — Plesiosauridce, 



47 



Plesiosaurid^. — In Wall-cases N'os. 9 and 10, and in Table- piiosaurus. 



case No. 6, are placed the remains of one of our lai-gest marine Wall-case, 



reptiles, the Piiosaurus, from the Kimmeridge Clay, near Ely, ^°- ^^• 



and also from Dorsetshire. We have no entire skeleton of this Table-case, 

 animal, but the cast of a swimmmg-paddle (the oi-iginal of 



Fig. 63.— Sauropterygian mandibles, a, Peloneustcs philarchus (Seeley) ; from the 

 Oxford Clay, 5. b, Thaumatosauriis indicus (Lydekker) ; Upper Jurassic of India, f. 

 c, PUsiosauras dolickodirus (Conybeare); from tlie Lower Lias, Lyme Regis. 



which is preserved in the Dorchester Museum) measures 7 feet 

 in length ; its jaw was 6 feet long, and one of its teeth was 15 

 inches in length. It had a shorter neck than the Plesiosaurus, 

 but was probably less fish-like in aspect than Ichthyosaurus, 

 which latter reptile it outrivalled in point of size. 



In Wall-case 'No. 13, and in Table-cases ]S"os. 6, 7, 8, are 

 arranged examples of the extinct group of marine reptiles, the 

 Plesiosauria (see Figs. 64, 65, pp. 48, 49). They are distinguished i^q^Iq^^^^ 

 at once by the great development of the neck, which is composed Table-cases, 

 of numerous vertebrae. The head is comparatively small in Nos. 6, 7, 8. 

 size ; the orbits are large ; the limbs being shaped externally 



Plesio- 

 saurus. 



