550 Geological Society, 



acids generated and condensed together did not form two separate 

 strata of liquid. 



Sulphides were in some cases converted into chlorides ; in other 

 cases not so ; in nearly all cases a trace of whitish sublimate was pro- 

 duced in the gaseous acid. The chlorate and nitrate of potash were 

 both decomposed. 



I may here take the opportunity of stating that tubes charged with 

 liquid carbonic acid in October 1860 suffered no leakage by Febru- 

 ary 1865. 



GEOLOGICAL SOCIETY. 

 [Continued from p. 405.] 

 April 26, 1865. — W. J. Hamilton, Esq., President, in the Chair. 

 The following communications were read : — 



1. " On the Character of the Cephalopodous Fauna of the South 

 Indian Cretaceous Rocks." By Dr. F. Stoliczka. 



In this paper the author gave a summary of the more important 

 facts brought to light by the examination of the Cretaceous Cepha- 

 lopoda of Southern India, which was begun by Mr. H. F. Blanford, 

 and continued by himself, giving, first of all, a brief notice of what 

 had been done previously by other observers, and a sketch of Mr. 

 Blanford's subdivision of the strata into the Ootatoor (or Lower), the 

 Trichinopoly (or Middle), and the Arrialoor (or Upper) groups. All 

 the genera characteristic of European Cretaceous faunae were stated 

 to be well represented, the whole assemblage having a Middle Cre- 

 taceous aspect. The number of species of the different genera oc- 

 curring in each of the three subdivisions was then given, as also 

 the distribution of the groups of the genus Ammonites- — the most 

 striking and abnormal feature being the intimate association of three 

 species of that genus, belonging to the Triassic group " Globosi," 

 with true Cretaceous fossils. Dr. Stoliczka then discussed the 

 relation of this Indian fauna to those of the European Cretaceous 

 rocks, and illustrated his remarks by a table showing the geological 

 range in India and in Europe of the species that are common to 

 both areas. He came to the conclusion that for the present the 

 lowest of Mr. Blanford's subdivisions (the Ootatoor group) may be 

 considered to be of the age of the European Gault; while the 

 uppermost (the Arrialoor group) does not seem to correspond to a 

 higher division than D'Orbigny's Senonien. 



2. " On the Growth of Flos Ferri, or Coralloidal Arragonite." 

 By W. Wallace, Esq. 



The author first described the physical features of the Meldon 

 Mountains, in Westmoreland, and endeavoured to show that they 

 bore certain relations to the geological structure of the country, and 

 that the number and size of the joints varied with the elevation of 

 the rocks, and their position in relation to the valleys. After the 

 formation of the joints, the minerals occurring in the veins in their 

 neighbourhood were stated to be acted upon by decomposing-agents, 

 and it was therefore inferred that the amount of decomposition in 



