270 Geological Society. 



and each of the more important sections of a genus at least, are 

 illustrated in the text, while all species that have not been satis- 

 factorily figured elsewhere, are, as far as possible, to be represented 

 on the coloured plates. These are issued and sold separately — a 

 great advantage for working entomologists, who frequently require 

 more than one copy of a work of this description ; and it would be 

 too much to expect them to buy a duplicate set of coloured plate3 

 too. We regret that both the plain and coloured figures represent 

 one side of the insect only ; but this inartistic method was abso- 

 lutely unavoidable without a very large (and, for scientific purposes, 

 unnecessary) additional outlay of both space and money. 



We hope Sir George Harapson may live to bring out many 

 more volumes similar to the book now before us. 



PROCEEDINGS OF LEARNED SOCIETIES. 



GEOLOGICAL SOCIETY. 



November 9th, 1898.— W. Whitaker, B.A., F.R.S., 

 President, in the Chair. 



The following communication was read : — 



' On the Radiolaria in the Devonian Rocks of New South Wales.' 

 By G. J. Hinde, Ph.D., F.R.S., E.G.S. 



Hand-specimens of the various radiolarian rocks discovered by 

 Messrs. David and Pittman in New South Wales were forwarded 

 to the Author, and from them numerous microscopic sections were 

 prepared. In the chert and jasper rocks of the Jenolan, Bingara, 

 and Tamworth districts, the radiolaria were for the most part in 

 the condition of casts filled with cbalcedonic silica and without 

 structure, so that their generic characters could not be determined. 

 Also in the claystones, the radiolaria were but poorly shown in 

 sections, though the structure could be seen in specimens weathered 

 out naturally on the surface of the rock. But in the siliceous 

 limestones and in the volcanic tuffs the radiolaria were embedded in, 

 and infiltrated with calcite, and by careful etching of thin sections 

 of the rock, the lime was eliminated and the organisms were shown 

 very distinctly. The rock then appeared as a confused mass of 

 entire and fragmentary radiolaria and minute debris of their spines 

 and latticed tests. The silica of these forms is for the most part 

 still in its colloid condition ; in some, however, it has been replaced 

 by a dark mineral. 



Fifty-four species belonging to 29 genera have been determined 

 and figured ; all the species and four genera are regarded as new ; 

 excepting a few primitive types of Nassellaria, the forms belong to 

 the Spumellaria. The large majority may be included in the 



