120 Geological Society : — 



horizon of the Chalk Rock, does not exceed 1| foot in thickness and 

 persists for a few yards only. In composition and microscopic cha- 

 racter it presents a close analogy to the Taplow phosphatic deposit, 

 which, however, occurs at the top of the Upper Chalk. Like it, it 

 consists of "brown phosphatic grains embedded in a white chalky 

 matrix. The grains include a large number of pellets, attributable 

 to small fish, phosphatized foraminifera, chips of bone, &c. Fish- 

 teeth also occur in abundance. 



To complete the resemblance, the Lewes deposit rests on a floor 

 of hard nodular chalk, beneath which is a white chalk traversed by 

 irregular branching pipes filled with the brown variety. Such 

 * floors ' are attributed to concretionary action ensuing upon a pause 

 in the sedimentation. The piped chalk is compared with the 

 structure known as Spongia paradoxica. 



It is concluded that phosphatized deposits may occur at any 

 horizon in the Chalk ; that the phosphatization is due to small fishes, 

 attracted by an unusual abundance of food ; that they are shallow- 

 water deposits, and associated with a pause or change in the sedi- 

 mentation. 



Mr. Chapman furnishes a list of 42 species and varieties of 

 foraminifera and 6 species of ostracoda. The former indicate a 

 deeper water origin than do those of the Taplow Chalk. He notes 

 the occurrence for the first time in this country of Gypsina Coetce, 

 Marrson. 



3. ' On the Classification of the Strata between the Kimeridgian 

 and the Aptian.' By Dr. A. P. Pavlow, Professor of Geology in the 

 University of Moscow, For.Corr.G.S. 



In this paper the author discusses the new evidence respecting 

 the palaeontology of the Lower Cretaceous and Upper Jurassic 

 deposits of Russia which has come to light since the publication by 

 himself and Mr. Lamplugh of ' Les Argiles de Speeton et leurs 

 Equivalents ' (Moscow, 1892). He is now enabled to fix with 

 certainty the zones of Hoplites riasensis and Olcostephanus hoplitoides 

 of the provinces of Riasan and Simbirsk, and is thus in a position 

 to correct and complete his former classification of the Upper 

 Jurassic and Lower Cretaceous rocks of Russia, and to define more 

 strictly their relationship equivalent to the strata of other countries. 



The whole of the Petchorian Series — that is, the zones of 

 Ammonites stenomphalus and Amm. Keyserlingi — is now regarded 

 as Lower Neocomian of a hitherto unknown boreal type, notwith- 

 standing the affinity of its fauna with that of the underlying 

 Jurassic (Aquilonian) strata. The author is thus led to carry up 

 into the Cretaceous the corresponding stages in Western Europe, 

 including the upper part of the zone of Belemnites lateralis of Speeton 

 and Lincolnshire, the Upper Berriasian of South-eastern Prance, 

 and probably the Hils Beds of German}-, instead of classing these 

 with the Jurassic as he had previously done. 



A table is given in which the detailed correlation of the rocks 



