JAN 2:> lDi)6 



C 11 1 e n t s. 



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Preface V 



Historical Survey of the knowledge regarding the development of the whale 1 



On the development of Lagenorhynchus acutus, Gray 9 



On the development of Lagenorhynchus alhirostris, Gray ^5 



The earlier stages in the development of Phocæna communis, Lesson 31 



Some stages in the development of Orca gladiator, La Cépéde 41 



Contributions to the knowledge of the fee tal membranes in the Odontoceti 49 



On the duration of gravidity in certain Odontoceti. , 61 



Literature, general and special 67 



Explanation of the Figures, with VII Plates 71 



