40 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



On the Structure and Affinities of the HippuRiTiDiE. 

 By S. P. Woodward, Esq., F.G.S. 



[Platks III. IV. v.] 



[Read May 24, 1854*.] 



CONTENTS. 



Introduction. 



Description of the Shell of the Hippurite. 

 Genera related to Hippurites : ' 



Radiolites. 



Caprotina. 



Caprina. 



Caprinella. * 

 Requienia. 

 The Hippuritida and their Geological Distribution. 

 Affinities of the Hippuritidce. 



Critical examination of the opinions of earlier observers. 



Hippuritidce referred to Corals, Annehds, and Cirripeds. 



to Palliobranchiates. 



to a separate Molluscan Order (Rudista). 



— to Lamellibranchiates. 



Description of some New Species of Hippurites and Radiolites. 



Introduction. — It is now forty years since Mr. Parkinson, the most 

 distinguished palaeontologist of his day, read a paper before this 

 Society, descriptive of some Hippurites from Sicily. The paper was 

 printed in the second volume of the * Transactions' (p. 277); the spe- 

 cimens are yet in the Society's Museum. Mr. Parkinson adopted the 

 notion of Baron Picot de Lapeirouse, that Hippurites were chambered 

 shells related to Orthoceras, and pointed out the means by which he 

 thought they might have been capable of " raising themselves occa- 

 sionally to the surface of the sea " (loc. cit. p. 282). 



Since that time many eminent palaeontologists have devoted atten- 

 tion to the subject ; but, owing doubtless to the incompleteness of 

 their materials, scarcely two authors have formed a similar opinion, 

 and some of the latest-published views are more improbable than 

 those promulgated by Mr. Parkinson. 



The collection of Hippurites and allied fossils in the British Mu- 

 seum has been rendered so complete by the liberality of Mr. S. 

 Peace Pratt and Sir Roderick I. Murchison, and by the assistance of 

 Dr. Krantz of Bonn and M. Saemann of Paris, as to leave very little 

 to be desired in the way of additional data. It is due to M. Saemann 

 to say, that some of the most instructive specimens were procured 

 by him with his own hands, and that he was fully aware of their 

 scientific value. 



My own observations, so far as they are new, would be scarcely 



* For the other communications read at this Evening Meeting, see Quart. Journ. 

 Geol. Soc. vol. X. p. 397. 



