324 



THE WONDERS OF GEOLOGY. Lect. IV. 



species swarm in our seas, and are abundant in the sandy 

 clays which are spread over great part of Cambridge- 

 shire, Lincolnshire, &c. Mr. Williamson of Manchester, and 

 Mr. Smith of March, have sent me specimens of this sand, 

 principally made up of these shells, with those of Lageniila, 

 Spiivloculina, &c* 



The common generic forms of the English chalk, and 

 some of the species, have been found in the cretaceous strata 

 throughout Europe, Asia, and America. From numerous 

 localities of America I have obtained, through the liberality 

 of Dr. Bailey, f earths largely composed of these fossils. 

 Mr. Lyell has figured, from the cretaceous beds of New 

 Jersey, a Rotalina and Cristellaria, identical with English 

 species. $ 



19. Chalk detritus at Charing. — I must conclude 

 this notice of the cretaceous polythalamia, by directing 

 attention to a remarkable deposit, first observed by W. 

 Harris, Esq. of Charing, Kent, to whom I am indebted for 

 an extensive suite of the prevalent species. Near Charing, 

 there is a bed about a foot thick of chalk detritus, consist- 

 ing of white sandy tenacious clay, spread over the outcrop, 

 or exposed surface of the firestone ; and which has evidently 

 originated from the action of water on the unconsolidated 

 chalk of the neighbouring downs, before the surface of 

 those hills was protected by a covering of vegetable soil. 

 This debris is largely made up of shells of numerous kinds of 



* See a highly interesting paper on Foraminifera from the Levant, 

 Boston, and Charing, by W. C. Williamson, Esq. in vol. viii. of the 

 Manchester Literary and Philosophical Society, 1847. 



f Dr. W. Bailey, Professor of Chemistry in the U. S. Military 

 Academy of West Point, New York, a gentleman eminently distin- 

 guished for his scientific attainments, has elaborately investigated the 

 fossil infusoria and foraminifera of the United States, and published 

 the result of his researches in several successive numbers of the Ameri- 

 can Journal of Science. 



J Geol. Proc. for 1845-6, p. 4. 



