Notes on the fossil corals collected by Mr. A. P. Low at Beechey Island, Southampton Island and Cape Chidley, in 1904.
(By Lawrence M. Lambe, F.G.S., F.R.S.C.)
BEECHEY ISLAND, LANCASTER SOUND.
Acervularia austini (Salter). 1852. Sutherland’s voyage[*], appendix, p. ccxxx, Strephodes? Austini, pl. 6, figs. 6, 6a.
The type specimens of this species were obtained at Cornwallis, Beechey and Griffiths islands. A number of corals in Mr. Low’s collection, from Beechey island, appear to belong to this species, judging from Salter’s description and figures and those of Houghton in the Journal of the Royal Dublin Society, vol. 1, 1856-57 (1858), p. 246, pl. X., figs. 2, 2a.
In Mr. Low’s specimens the inner structure is fairly well shown. The larger septa pass to the centre of the corallites where they are slightly twisted, and together with the arched, rather vesicular tabulæ, form a definite central area that appears at the bottom of the cups as a more or less distinct boss. The septa (averaging from thirty to forty in number) bear arched carinæ on their sides. The corallites are slightly larger than those of A. gracilis[†] (Billings), from Grand Manitoulin island, Lake Huron (Niagara group), otherwise the specimens could with equal propriety be referred to the Lake Huron species. The size of the corallites varies in A. austini from about 3 to 8 mm. in diameter, in Mr. Low’s specimens up to about 10 mm. across, but in A. gracilis the corallites seldom reach a diameter of 7 mm. If by a direct comparison it is found that Mr. Low’s specimens are without doubt properly referable to A. austini, and if it can be shown that the size of the corallites cannot be relied on as a specific character, then A. gracilis may have to be regarded as identical with A. austini.
Two specimens of corals from Beechey island are not referable to any genus with which the writer is acquainted. In these specimens the structure is revealed, by weathering at the calicular surface and in horizontal and longitudinal sections, as well as in sections obtained by rubbing down and polishing. As the writer is unable to place this coral, to his satisfaction, in any described genus, it is thought best to establish a new genus for its reception. The main generic characters are enumerated below with a brief description of the species which the writer has much pleasure in naming after Mr. Low.
| [*] | Journal of a voyage in Baffin’s bay and Barrow straits in the years 1850-1851 by Peter C. Sutherland, M.D., M.R.C.S.E., 1852. |
| [†] | Strombodes gracilis. 1865 Geological Survey of Canada, Palæozoic Fossils, vol. 1, p. 113, fig. 94, by E. Billings; and Acervularia gracilis, 1900, Contributions to Canadian Palæontology, vol. IV, pt. II, pl. XIV, figs. 2, 2a, by Lawrence M. Lambe. |