Preliminary Report On the Paleontology of the Black Hills

o lines in width and of an indefinite length, with rounded or obtusely-pointed extremities. The examples in the collection before us are coiled, forming irregular curves, usually enrolled, but sometimes sigmoidal. The surfaces are smooth and structureless, presenting no marking whatever, although tlie substance is usually of a somewhat lighter color than the surrounding rock. The terminations are usually sharply rounded, and the whole appearance is more that of the impression of an Annelid than of a plant, though it is difficult to conceive of the preservation of anything other than a plant to leave such markings. We have referred them to the above genus, presuming them to be congeneric with those figured by Professor McCoy in his Synopsis British Palreozoic Fossils, plate 1 A, fig. 3, although they are not elevated or rounded bodies, but flattened stipes. Formation and locality.?In the plant beds of the Potsdam formation (probably Upper Potsdam or Calciferous), Head of Red Water Valley, Black Hills, Dakota. Genus PAL.EOPHYCUS, Hall. Palophycus Occidentalis, n. sp. Plate 1. fig. 3. Remains consisting of strong, subcylindrical, flexuous stems or roots, covering the surface of the sandstone. The steins are more or less rounded, although frequently quite flattened, and varying in diameter from one-fourth of an inch to one inch, frequently bifurcating and sometimes dividing into threes. They are commonly interlaced with each other, but do not app...