Page:TransRoySocCanada 16 4 159-167.djvu/4

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the organism and includes them in the foraminifera under a new genus Moellerina as Moellerina greenei. The number of spirals are stated to be eight or nine. Ulrich's description and figures surpass in detail and accuracy any so far presented, and after a study of the Kelly's Island species the writer is convinced that Ulrich's description is applicable also to it. One discrepancy, however, is noted. Whereas all the specimens from Kelly's island examined by the writer, and apparently those by Knowlton from the Falls of Ohio, have a right handed spiral twist to the ridges, Ulrich figures one with a left handed twist. Only nine spirals were observed by the writer in the Devonian specimens to which he had access. But the number of spirals, as evident from the discovery of Palaeochara, does not mitigate against a possible Characeous affinity of this fossil. A much more serious objection may be raised. A feature carefully noted by Ulrich, and confirmed by the writer for the Kelly's Island species, is the presence not of a thick single wall as interpreted by Williamson, Dawson, and Knowlton, but of two thin walls with a broad intervening space, the inner spherical cavity communicating with the exterior by tubular prolongations of the inner wall at each end. The spiral ridges are restricted to the outer wall, and are a part or ornamentation of the wall itself, so that they afford no evidence of a Chara construction in support of the superficial appearance.

Class Crustacea

Subclass Eucrustacea

Anthrapalaemon hillianus Dawson

1877—Anthrapalaemon (Paloeocarabus) Hilliana, Dawson, Geol. Mag. Dec. 2, Vol. 4, p. 56. Figure 1.

1878—Anthrapalaemon (Paloeocarabus) Hillanus, Dawson, Suppl. 2nd ed. Acad. Geol. p. 55. Figure 10.

Description: (Based on a flattened carapace.) Carapace barrel-shaped, subquadrangular, greatest width exceeding the length exclusive of rostrum. Anterior margin straight, furnished with three marked spines, one rostral, long and thin, triangularly keeled, and an antero-lateral spine on each side, short and stout, flattened, diverging outwards from an angle of 30°. Lateral margins conversely rounded, provided in the anterior one-third with short spines or serrations, directed forwardly. Posterior margin, grooved, concavely rounded, joining the lateral margins in bluntly acute angles.