The Canadian journal of industry, science and art . arge siphuncle. The latter often contains Fig. 132. a cone of calcareous matter, as in Endoceras proteiforme. The type, as yet, is comparatively rare, but a specieshas been discovered in the Calciferous Sand Rock of the MinganIslands, by Sir William Logan and Mr. Richardson. This is de-scribed by Mr. Billings in the Ganadian Naturalist, Vol. V., p. making Piloceras, however, merely a sub-genus of Gyrtoceras, asexplained above, we follow our own views. Fhragmoceras:—This genus, in form, is closely allied to Gyrto-ceras, and is also conf
The Canadian journal of industry, science and art . arge siphuncle. The latter often contains Fig. 132. a cone of calcareous matter, as in Endoceras proteiforme. The type, as yet, is comparatively rare, but a specieshas been discovered in the Calciferous Sand Rock of the MinganIslands, by Sir William Logan and Mr. Richardson. This is de-scribed by Mr. Billings in the Ganadian Naturalist, Vol. V., p. making Piloceras, however, merely a sub-genus of Gyrtoceras, asexplained above, we follow our own views. Fhragmoceras:—This genus, in form, is closely allied to Gyrto-ceras, and is also confined to Palaeozoic rocks. The shell is curved,and the septa simple or slightly sinuated; but the aperture of theshell is more or less strongly contracted. The siphuncle is variable>although in most species hitherto referred to Phragmoceras, it liesalong the shorter curve of the shell. In the Bohemian P, perversumof Barrande, and in the P. prcematurum of Billings, it occupies,nevertheless, the convex side. Fig. 133 represents a fragment of the. MINERALS AND GEOLOGY OF CANADA. 23 latter species (after Billings), from the Black River Limestone of LaCloche Island, Lake Huron.
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