Mr. A. Bell on the Fauna of the Mud-deposit of Selsey. 45 



false ova we regard as the less justifiable because, according 

 to our observation already communicated, the development of 

 the embryo also takes place in the winter ova without pre- 

 vious fecundation by the male. 



Of course our opinion will lose nothing, even should it in 

 time be proved that no evolution takes place without fecunda- 

 tion in the animal kingdom, i. e. that the cases of partheno- 

 genesis and psedogenesis are only cases of self- fecunda- 

 tion. 



It will not be superfluous to remark here, that in my judg- 

 ment the fate of the parthenogenesis of plants awaits the 

 theory of the agamic reproduction of some animals. As in 

 the former case the parthenogenesis set up by Radlkofer and 

 Alex. Braun has been brought down to the grade of ordinary 

 hermaphroditism by the investigations of Kegel, Karsten, 

 De Bary, Schenk, and many others, so also it will probably 

 be proved for the animal kingdom that some parts of the 

 ovary produce spermatozoa instead of ova — which, indeed, may 

 very easily be possible, as the ovary and the testis are origi- 

 nally perfectly similar structures. 



Not long since I learned that H. Balbiani is now publishing 

 his memoir upon the Aphides, in which he endeavom-s to de- 

 monstrate the hermaphroditism of those insects ; and thus the 

 supposition above expressed is already confirmed. Unfortu- 

 nately I have been unable to make myself acquainted with 

 this work. 



[To be continued.] 



V. — Contributions to the Fauna of the Upp>er Tertiaries. 

 No. I. The " Mud-dejposit " at Selsey, Sussex. By Alfeed 

 Bell. 



It is now some twenty years since Mr. Dixon, of Worthing, 

 called the attention of geologists to a superficial deposit upon 

 the sea-shore of the Sussex coast, near Selsey, eight miles 

 south of Chichester, to which he gave the name of " mud- 

 deposit." This deposit was afterwards fully described by Mr. 

 Godwin- Austen in a paper upon the Newer Tertiary Deposits 

 of the Sussex Coast, read before the Geological Society and 

 published in their ' Quarterly Journal,' 1857. Both these 

 gentlemen gave lists of fossils ; but, owing to unfavourable 

 circumstances, the beds or scattered patches being very inac- 

 cessible, and only workable at low tides, the lists only enume- 

 rate about forty-five species of various organisms. Some 



