122 PALEONTOLOGY 



pulmonates are found, but there are a few terrestrial 

 forms, such as Dendropupa and Archaoxonitts, genera 

 almost identical with the Pupa and Zonites (allied to 

 Helix) of to-day. The oldest known freshwater pul- 

 monates appear to be Physa and Planorbis of the 

 Purbeck beds. 



Short Bibliography. 



(See under " Mollusca Generally," p. 92.) 



GRABAU, A. W. (i) Studies of Gastropoda, American 

 Naturalist, vols. xxxvi., xxxvii., xli. (1902-07); (2) Phy- 

 logeny of Fusus, Smithsonian Misc. Coll., vol. xliv. (1904); 

 (3) the above are summarized in Grabau's Principles of 

 Stratigraphy, p. 967 et seq. 



MONOGRAPHS OF THE PAL^ONTOGRAPHICAL SOCIETY. 



BLAKE, J. F. Fauna of the Cornbrash (1905 07). 



HARMER, F. W. Pliocene Mollusca, vol. i. (1913-19) 



HUDLESTON, W. H. Gastropoda of the Inferior 

 Oolite (1887-96). 



MORRIS, J., AND LYCETT, J. Great Oolite Mollusca, 

 with Supplement (1850-63). 



SLATER, I. L. British Conulariae (1907). 



WHIDBORNE, G. F. Devonian Fauna (1889-1907). 

 Gastropoda in vols. i. and iii. 



