Acipenser albertensis

Lambe L. M., 1902, New genera and species from the Belly River Series (mid-Cretaceous), Geological Survey of Canada Contributions to Canadian Palaeontology 3, pp. 25-81 : 29

Acipenser albertensis Sp. nov.

Plate XXI, fig. 9 .

The strongly keeled and highly ornamented shield shown on plate XXI , apparently represents an ancient sturgeon, for which the above name is proposed. The ornamentation consists of rounded, coalescent ridges and nodes in high relief, and quite smooth, not very unlike the sculptured surface of the shell of some species of turtles.

This genus has not hitherto been known from rocks lower than the Tertiary.

Belly Eiver series, Eed Deer river, District of Alberta, 1901.

Figures

PLATE XXI. Fig. 1. Stegoceras validus, Lambe, prenasal bone; side view. Natural size. Page 63. Fig. 2. The same, inferior aspect. Fig. 3. Superior view of another specimen; natural size. Fig. 4. The same; side view. Fig. 5. The same; inferior view. Fig. 6. Stereocephalus tutus, Lambe, symmetrical plate, superior aspect; one-half the natural size. (Pro. visionally associated with S. tutus). Figs. 7 and S. Similar keeled plates one-half the natural size. Fig. 9. Shield of Acipenser albertensis, Lambe, viewed from above. Natural size. Page 29 .

PLATE XXI. Fig. 1. Stegoceras validus, Lambe, prenasal bone; side view. Natural size. Page 63. Fig. 2. The same, inferior aspect. Fig. 3. Superior view of another specimen; natural size. Fig. 4. The same; side view. Fig. 5. The same; inferior view. Fig. 6. Stereocephalus tutus, Lambe, symmetrical plate, superior aspect; one-half the natural size. (Pro. visionally associated with S. tutus). Figs. 7 and S. Similar keeled plates one-half the natural size. Fig. 9. Shield of Acipenser albertensis, Lambe, viewed from above. Natural size. Page 29