FOUND IN CANADIAN ROCKS—WESTON. 5 
Ammonites and crustaceuns occur. Among these are Ammonites 
(Desmoceras), Sacya (Forbes), and Ammonites (Haploceras), 
Beudanti, Brongniart. 
8. The Huronian rocks, which I have described above, Fig. 1, 
contain many curious concretions. Some of the small islands 
in Georgian Bay are composed of a calcareous greenstone, in 
which an aggregate of quartz, feldspar, chlorite, epidote, etc., are 
found. In this rock concretionary balls an inch in diameter 
occur, microscopic sections of which show them to be composed 
of the same material as the matrix in which they are imbedded, 
both being highly crystalline, and the concretions having a 
scoriated appearance. 
9. A soft, whitish limestone from the Cambrian deposits of 
Cow Head, Newfoundland, is composed chiefly of rounded grains 
of irregular shape and size, many of which might readily be taken 
for Ostracod crustaceans, or have a close resemblance to the 
species Conodona Tateana. The microscope, however, shows 
them to be concretious, generally partly hollow and filled with 
crystalline hmestone. In the beds from which the specimens 
examined came, ten species of trilobites have been found by 
Dr. Ami of the Geological Survey of Canada. 
10. An oolitic limestone from the Cambrian rocks of the 
Selkirks, B. C., two miles west of Donald, shows under the micro- 
scope concentric layers, slight radiating lines and crystalline fibres 
arranged at various angles transverse to the concentric structure. 
Fig. 2 is from a micro-drawing of one of these forms, enlarged 
about 20 diameters. 
