280 



Antediluviati Zoology and Botany. 



On the Continent this department was illustrated as early 

 as 1775, in Knorr's magnificent Recueil des Monumens des 

 Catastrophes que le Globe de la Terre a essuiees. 



Mr. Sowerby's Mineral Concliology of Great Britain com- 

 prehends the greater portion of our fossil shells. Numerous 

 additional species have, however, been described in other 

 works; such, for instance, as those by Messrs. Young and 

 Bird, Mr. J. Phillips, Mr. Mantell *, and by contributors 

 to the Trans, Geol. Soc. From sources so authentic, it is 

 possible to form estimates which will now convey some notion 

 of the numbers, the prevalence, and the geological distribution 

 of our mineralised Test^cea. The augmentation which such 

 a table is capable of receiving is not, in one point of view, 

 very material ; because it is not probable that the relative 

 proportions which the respective classes bear to each other 

 will be much affected by such addition. Proceeding at once 

 to the result, the numbers and proportions are as follows : — 



Simple Univalves, Gasteropodous Mollusca - 

 Simple Bivalves, Acephalous MolMsca 

 Complicated Bivalves, in ancient formations 

 Multilocular, or cham- > ri i, ^ j tv/tit lo lo 



bered UniValves - \ Cephalopodous Mollusca - 12 - 12 



- 62 to 64 genera. 



- 69 or 71 

 - - 3— 3 



In all 146 to 150 genera. 



The geological distribution of species comprised within 

 these genera is found to be in the following manner : — 



This number falls greatly short of the entire series. M. Deshayes has 

 determined no less than 1200 species in the tertiary deposits alone of the 

 Paris basin. 



* Mr. Mantell's Tabular Arrangeme7it of Sicssex Fossils, recently published 

 by the Geological Society, furnishes an admirable condensation of local 

 zoological information. Mr. J. Phillips's tables are also arranged with 

 great care and ability. 



