1854.] PRESTWICH LONDON CLAY. 411 



have, during the last few years, advanced most materially, and given 

 an unusual completeness to most branches of Tertiary palaeontology*. 

 The Report also by Professor Agassiz, in 1844, on the fossil fishes of 

 the London Clay is a monograph of the greatest value, and presents 

 us with a research such as few other strata have undergone f. The 

 Crustacea yet offer a rich and almost unexplored field ; Professor 

 M'Coy has, however, described a few species J. Mr. R. Jones has 

 commenced an examination of the Foraminifera and Entomostraca, 

 which will, it is hoped, be continued. 



[Parts of these lists will be found more complete than the rest, in consequence 

 of some groups of fossils and some beds having been the object of more 

 especial research than others. Many species will probably be found to have 

 a greater range. The prevalence, however, of certain fossils at certain levels 

 is the essential and prominent feature. An asterisk marks the common and 

 characteristic shells ; I cannot at present safely apply it to the other groups.] 



First Zone. — Isle of Sheppey Fossils {cliff-section). 



AVES. 

 Halcyornis Toliapicus, Owen. Lithornis vulturinus, Owen. 

 {Larus, Kon.) (?) Emuinus, Bowerb. 



Reptilia. 



Chelone breviceps, Owen. Emys Delabechii, Bell. 



convexa, Owen. leevis, Bell. 



cuneiceps, Owen. testudiniformis, Owen. 



latiscutata, Owen. Platemys Bowerbankii, Owen. 



longiceps, Owen. Bullockii, Owen. 



subcarinata, Owen. Trionyx pustulatus, Owen. 



subcristata, Owen. Crocodilus champsoides, Owen. 



Emys bicarinatus, Bell. ToUapicus, Owen. 



Comptoni, Bell. Palaeophis Toliapicus, Owen. 



Pisces. 



Acestrus omatus, Ag. Auchenilabrus frontalis, Jg. 



Acipenser Toliapicus, Ag. Bothrosteus minor, Ag. 



iEtobatis irregularis, Ag. Brachygnathiis tenuiceps, Ag. 



subarcuatus, Ag. Brychetus Mulleri, Ag. 



Ampheristus Toliapicus, Kijn. Calopomus porosus, Ag. 



* The following very important monographs on the Eocene fossils have already 

 been published : — 



Professor Owen and Professor Bell, " On the Chelonia of the London Clay," 1849. 



Mr. F. E. Edwards, " On the Cephalopoda of the Eocene Formations," 1849. 



Professor Owen, " On the Crocodilia and Ophidia of the London Clay," 1850. 



Milne-Edwards and J.Haimes, "On the Corals of the Tertiary Formations," 1850. 



Mr. Charles Darwin, " On the Fossil Lepadidse of Great Britain," 1851. 



Mr. Thos. Davidson, " On the British Tertiary Brachiopoda," 1852. 



Professor E. Forbes, "On the Echinodermata of the British Tertiaries," 1852. 



Where the London Clay is spoken of in these monographs it is generally under- 

 stood to include the Bracklesham sands and the Barton clays. I restrict the 

 term to the lower deposits of London and of Hampshire. 



t Report of the Brit. Assoc, for the Advancement of Science, 1845, p. 279. This 

 has been further revised and added to by Sir Philip Egerton in Mr. Dixon's 

 " Geology of Sussex," and in the edition just published of Morris's Catalogue. 

 I avail myself of the assistance afforded by this latter very valuable work, which 

 has reached me as this paper is going through the press, in the final revision of the 

 lists in the text. — J. P., August 1854. 



X Ann. and Mag. Nat. Hist. 2nd Ser. 1849, vol. iv. p. 161. 



