THE YOUNG NATURALIST. 



Ill 



of the bed are seen resting on the Lower Greensand. Folkestone has always 

 been a famous place for collecting Gault fossils, and it has been divided into 

 the following zones : 



Upper Gault (about 72 feet) — Zone of Ammonites rostratus, Kingena lima, 



Ammonites varicosus, A. cristatus (Nodule Bed). 

 Lower Gault (about 28 feet) — Ammonites auritus (Dark Bed), A. denarius 

 Mottled Bed), A, lautus (Coral Bed), A. Be la Ruei, Crus- 

 tacea (Paleeocorystes) ', Ammonites auritus, A. interruptus. 



Among the chief fossils of the Gault are the following : 

 Folkestone. 



Aeoncea tenuicosta, Alaria carinella, Ammonites auritus, A. benittice, A. 

 carnatus, A. aenarius, A. Goodhallii, A. interruptus, A. lautus, A. mam- 

 millaris, A. splendus, A. tuberculatus, A. rostatus, A. velleda, Ancyloceras 

 opingerata, Apporhais Orbignaiana, A. ParJci?isoni, Belemnites aitenuatus, 

 B. minimus, Bellerophina minute, Buccinum gaultinum, Cadulas Gaulti- 

 nus, Cardita tenuicosta, Cidaris Gaultina, Cucnll(jea carinata, C. glabra, 

 Cyprina regularis, Dentatium decussatum, D. ellipticum, Exogyra conica, 

 Etyus Martinii, Fusus rusticus, F. Smithii, Gervilla solenoides, Gastro- 

 chana pyriforma, Hamites attenuatus, H. compressus, H. intermedins, II. 

 maxinus, H. tenius, H. tuberculatus, Hemiasterasterias, Helicocerus rotun- 

 dm, Inoceramus concentrieux, 1. solenoides, I. sulcatus, Lima parallela, 

 Leda Maries, Lucina tenera, Mytilus Gaultiennei, Natici Clementina, 

 N. gaultina, N. saultina, Nautilus inagualis, Nucula bivirgata, N. orna- 

 tissima, N. pectinata, Ostrea frons, Plicatula pectiroides, Peclen quadri- 

 costatus, P. quinquecistatus, P. Rauliniana, Panopcea plicata, Pholadidea 

 conslricla, Palceocorystes Broderipii, P. Stokesii, Pentacrinus Fitloni, 

 Rissoina incerta, Rostellaria carinata, Solarium conoideum, S. ornatum, 

 Serpula plexus, S. antiquata, Trigonia Filtoni, Trochus decussatus, Turitella 

 Vilrayeana, Turrlites elegans, T. catenatus. Venus tenora. 

 Maidstone. 



Aclcsn affiinis, Dentalium ellipticum, Lima parallela JJncula ovata, Sola- 

 rium ornatum. 



THE UPPER GREENSAND. — This formation is very thin indeed in 

 Kent. North of Folkestone and in Eastwear Bay we see greenish sandy beds, 

 about 20 feet thick, lying above the gault. Inland there is no exposure 

 except in the brick pits where the gault clay is dug. 



THE CHALK. — This formation may be described as a soft white lime- 

 stone, for it is almost wholly composed of carbonate of lime, and it is charac- 

 terized in its upper part by nodules and bands of flint. The total thickness 



