534 report — 1878. 



SATURDAY, AUGUST 17, 1878. 



. The following- Papers were read : — 



1. On the supposed Radiolarians and Diatoms of the Car coniferous Bodes. ' 

 By Professor W. C. Williamson, F.B.S. 



At the meeting of the British Association in 1872, Mr. Carruthers described 

 some small objects to which he gave the generic name'of Traquairia, and which he 

 concluded were Radiolarian skeletons. A characteristic series of these objects 

 having been obtained. by the author, he felt compelled to reject Mr. Carruthers' 

 determination as to their nature. They are small spherical bodies, from which pro- 

 ject numerous slender and apparently muricated branching prolongations, which 

 have at a superficial glance the appearance of spines, but which were shown to be 

 something very different. The entire sphere is encased in a structureless membrane, 

 of which the supposed spines are tubular, thin-walled, cylindrical extensions, and 

 which in turn give off numerous symmetrically-arranged tubular branches, which 

 probably ramified in a mucilaginous (?) investment. Within this outer membrane 

 were one or two other capsular membranes, the innermost of which was found, in 

 several examples, to be filled with cells that bore every indication of being vege- 

 table tissues, being absolutely undistinguishable from similar cells found in the 

 interiors of macrospores, and of cryptogamic sporocarps found associated with the 

 Traquairia?. These combined features led the author to regard the germs as 

 belonging to the vegetable rather than to the animal kingdom, and to represent a 

 cryptogamic form of reproductive structure. 



The author further described the minute organisms found in some of the moun- 

 tain limestones of North Wales, and which have been regarded as Radiolarians by 

 some geologists. These appear to be wanting in true Radiolarian characteristics, 

 but most of them seem rather to have been hollow, calcareous spheres. It is the 

 opinion of Professors Roscoe and Schorlemmer that the substitution of carbonate 

 of lime for silica in these organisms is a most improbable occurrence, and one that 

 can only be deemed possible in the case of organisms whose originally siliceous com- 

 position is beyond the reach of doubt — which is very far from being the case in the 

 instances referred to. 



Some time ago, Count Castracane announced a discovery of numerous remains 

 of marine and fresh-water Diatoms in the siliceous ash remaining after coal had 

 been subjected to certain chemical processes, of which the Coimt recorded the 

 method. Dr. Roscoe permitted Mr. Smith, one of his able assistants, to make for 

 the author similar preparations of thirty examples of Yorkshire and Lancashire 

 coals, prepared according to Count Castracane's directions, in Dr. Roscoe's labora- 

 tory, under the eye of that distinguished chemist. There is every guarantee for the 

 correctness of these preparations, but none of them exhibit the least traces of 

 Diatomaceous structures. Hence the author concludes that, so far as his experience 

 enables him to judge, there are as yet no evidences of the existence of either 

 Radiolarians or Diatoms during the Carboniferous age. 



2. On some Fossils from the Northampton Sands. 

 By John Evans, D.C.L., F.B.S. , 8fc. 



These fossils from the ironstone beds of Duston, near Northampton, are casts 

 of lithodomous borings originally made in lumps of coral, impressions of which 



