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III. ^-On the Squaloraia. • 



By H. RILEY, M.D.^ 

 Communicated by Charles Stokes, Esq., F.G.S. 



[Read May 15, 1833.] 



XHIS interesting animal, oF which Plate IV. is an accurate representation*, 

 was discovered in the lias of Lyme Regis in 1831 by Miss Anning, associated 

 with the Saurian and other remains, for which that place has become so cele- 

 brated. 



It was purchased by John Naish Sanders, Esq., and deposited by him at 

 the Bristol Institution, where it now constitutes a part of that valuable and 

 improving collection. 



The form of this animal is so striking and peculiar, that the majority of ob- 

 servers have disagreed not only as to its genus, but even as to its class : for by 

 the generality it has been pronounced a Saurian, and by a few even a bird. 



Those who advocate the former of these opinions, are led to do so from the 

 form of its parietal bone and its elongated jaws. The latter character was 

 likewise the reason for supposing it to be a bird. 



But the absence of alveoli and teeth, and of respiratory openings ; the form 

 and number of the vertebrae ; the form of the thoracic and pelvic regions, 

 with their attached members, render the former opinion but little probable. 



The other supposition is so at variance with all the anatomical details of the 

 fossil, that we shall not trouble our readers with its discussion. For our own 

 part, we cannot avoid concluding that it is a cartilaginous fish, having many 

 points of resemblance to some of the Rays, but differing from them in several 

 important characters. 



The entire length from the end of the lower jaw to the fractured extremity 

 of the tail is 17^ inches. The greatest length of the head, 7| inches. 

 Breadth across the orbits, 3^ inches. Length of the remains of the vertebral 

 column, 10 inchesf. Extreme width, 5^ inches. 



* Copied by permission of M. Agassiz from Plate XLIL, vol. 3. of Les Recherches sur lei. 

 Poissons fossiles. 



t Nearly the whole of the remainder of the tail has been subsequently found, and measures • 

 rather more than ten inches, including about 240 vertebrae ; and is in the possession of Miss 

 Philpott. 



M 2 



