PROCEEDINGS OF THE SCIENTIFIC SOCIETIES OF LONDON. 131 



Laurentian Eocks of Canada." By J. W. Dawson, LL.D., F.E.S., 

 r.a.S. "With a Note bj W. B. Carpenter, M.D., F.E.S., E.G.S. 



At the request of Sir Wm. Logan, Dr. Dawson carefully examined 

 the laminated material thought by Sir William to have an organic 

 origin, and he found it to consist of the remains of an organism 

 which grew in large sessile patches, increasing at the surface by the 

 addition of successive layers of chambers separated by calcareous 

 lamina. Slices examined microscopically showed large irregular 

 chambers with numerous rounded extensions, and bounded by walls 

 of variable thickness, which are studded with septal orifices irregularly 

 disposed ; the thicker parts of the walls revealed the existence of 

 bundles of fine branching tubuli. Dr. Dawson therefore concludes 

 that this ancient organism, to which he gave the name of Eozoon 

 Canadensdj was a Foraminifer allied to Carpenteria in its habits of 

 growth, but of more complex structure, as indicated by the compli- 

 cated systems of tubuli. It attained an enormous size, and, by the 

 aggregation of individuals, assumed the aspect of a coral reef. 

 In a note, Dr. Carpenter corroborated Dr. Dawson's observations 

 on the structure and affinities of Eosodn, but stated also that, as he 

 considered the characters furnished by the intimate structure of the 

 shell to be of primary importance, and the plan of growth to have a 

 very subordinate value, he did not hesitate to express his belief in its 

 affinities to Numonulina. 



3. " On the Mineralogy of certain Organic Eemains found in the 

 Laurentian Eocks of Canada." By T. Sterry Hunt, Esq., M.A., 

 E.E.S., of the Greological Survey of Canada. Communicated by Sir 

 W. E. Logan, LL.D., F.E.S., E.G-.S. Mr. Sterry Hunt first referred 

 to the structure of Eozodn as made out by Dr. Dawson, and then 

 stated that the mineral silicates occurring not only in the chambers, 

 cells, and canals left vacant by the disappearance of the animal 

 matter, but in many cases in the tubuli, filling even their smallest 

 ramifications, are a white pyroxene, a pale-green serpentine and 

 pyrallolite, and a dark-green alumino-magnesian mineral which the 

 author referred to Loganite. The calcareous septa in the last case 

 are dolomitic, but in the other instances are composed of nearly pure 

 carbonate of lime. The author then gave the results of a chemical 

 analysis of specimens from the difi'erent localities, and dedaced there- 

 from the composition and affinities of Loganite. This mineral he 

 considered to be allied to chlorite and to pyrosclerite in composition, 

 but to be distinguished from them by its structure. In conclusion, 



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