Page:Cincinnati Quart. J. Sci. 2 273-274.djvu/2

274 as the lateral lobes; lateral lobes flattened two thirds the way out, where they abruptly curve downward, narrow slightly posteriorly; pleura straight and transverse, two thirds of their length, where they are geniculated, curving slightly backward, terminate in short mucronate spines.

Pygidium, mesial lobe composed of three segments, anterior segment largely developed, its extemities being produced into long stout spines, incurved toward their points; posterior margin a rounded ridge, curving backwards between the spines, forming a subtriangular depression, upon which, the two posterior segments are situated; entire surface finely granulated; upon the upper surface of the globose glabella the granulations are coarser, so as to be distinguished by the eye.

This species is related to S. granulata (Angelin), and S. salteri (Billings), but differs materially from the descriptions of those species.

Formation and locality: In the upper third of the Trenton Limestone, Trenton Falls, New York.

Through the kindness of U. P. James Esq., I have been permitted to copy the description (which will appear in the forthcoming volume of the Ohio Paleontology) of Plumulites jamesi, by Profs. Hall and Whitfield. It is as follows: