Remarks on the Geology of the Valley of MacKenzie River

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: 82 TRANSACTIONS OF THE epitheca is not removed, however, there seems to have been moderately distinct septal costae marking the positions of the septa. The dissepiments are likewise quite distinctly seen between the costae of weathered specimens. This is almost certainly the coral referred by Mr. Soweeby,...
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Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: 82 TRANSACTIONS OF THE epitheca is not removed, however, there seems to have been moderately distinct septal costae marking the positions of the septa. The dissepiments are likewise quite distinctly seen between the costae of weathered specimens. This is almost certainly the coral referred by Mr. Soweeby, in Sir John Richardson's collection, to AmplexuA, which it much resembles externally, though it differs widely from that genus in internal structure. Named in honor of Sir John Richardson. Locality and position. Mackenzie river, at the Ramparts, lat. 66 deg., long. 127 deg. Genus Zaphrentis Rafinesquk, 1820. Zaphrentis recta Meek. PI . XI, fig. 1. Corallum obconical, straight, or probably sometimes a little curved, rather attenuate at the lower extremity. Epitheca thick, strongly wrinkled, or, at irregular intervals, even constricted by the marks of growth, almost entirely concealing the septa. Calice circular, conical, and rather shallow; septal fossette lateral.very shallow. Septa thin and numbering in the primary series about forty, which alternate with as many imperfectly developed secondary ones; on grinding away the epitheca, about seven of these two sets may be counted in the space of 0.20 inch. TabulaB forming irregular vesicular cavities, apparently not very distinct from those formed by the dissepiments, excepting that they are larger and more transverse. Vesicles of the outer zone rather small and ranging obliquely outward and upward. Length, 1.70 inches; breadth, 0.95 inch; depth of calice, 0.33 inch. The septal fossette is so faintly marked in this species that it might be readily overlooked, and cause the coral to be referred to CyatJwphi/llum. The presence of the fossette, however, is obvious enough, when once the attention is drawn...