EXPLANATION OF THE PLATES AND WOOD-CUTS. 



PLATE XLIL 



Illustrates Mr. Owen's paper on the Dislocation of the Tail at a certain point, observ- 

 able in the Skeleton of many Ichthyosmiri : p. 51L 



All the tails represented in the accompanying plate belong to skeletons of Ich- 

 thyosauri now in London and formerly in the collection of Mr. Hawkins : and these 

 illustrations will not lose force from the fact of their being taken from figures of 

 those skeletons published without any reference to the structure or hypothesis in 

 question. 



Upper right-hand figure from a specimen found in the lias at Walton in Somer- 

 setshire. (See Mr. Hawkins's work on Ichthyosauri and Plesiosauri: p. 32. PI. 

 XVII.) 



Lower right-hand figure, from a specimen found in lias at Lyme Regis. (See 

 Mr. Hawkins's work, p. 25. PI. VII.) 



Middle figure. 1 



T n^ , J n } See the Second Part of Mr. Hawkins's work. 



Left-hand upper figure. J 



Left-hand lower figure from a specimen found in lias at Walton in Somersetshire. 



(See Mr. Hawkins's work, p. 34. PI. XXI.) 



PLATES XLIII. to XLV. 



Illustrate Mr. Owen's memoir on the Specimen of Plesiosaurus Macrocephalus (Cony- 

 beare) in the collection of Viscount Cole : p. 515. 



Plate XLIII. 



Reduced figure of Lord Cole's specimen, with comparative outline sketches of the 

 paddles oi Plesiosaurus Dolichodeirus and P. Hawkinsii: p. 515, et seq. 



Plate XLIV. : p. 518. 



Fig. 1. Diagram of vertebral elements : p. 518. 



Fig. 2. Caudal vertebra of a Python : p. 518. 



Fig. 3. Cervical vertebra of a Pelican : p. 518. 



Fig. 4. Cervical vertebra of Plesiosaurus Hawkinsii, natural size : p. 523. 



Fig. 5. Cervical vertebra of Plesiosaurus arcuatus, natural size. 



Fig. 6. Section of terminal caudal vertebras of Plesiosaurus : p. 528. 



Plate XLV. : p. 531. 



Head of Plesiosaurus Hatvkinsii and of Plesiosaurus Macrocejihalus. 



PLATES XLVL and XLVII. 



Illustrate Mr. Malcolmson's memoir on the Eastern Portion of the Great Basaltic Di- 

 strict of India : p. 537. 



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