Page:Walcott Cambrian Geology and Paleontology II.djvu/146

90 ridges are beautifully marked by irregular radiating ridges that branch quite irregularly and are united by irregular cross-ridges so as to give an anastomosing effect.

Dimensions.—The dimensions are shown by the figures on pl. 17, figs. 2 and 2a.

Observations.—The cranidium of this species is much like that of Anomocare læve (pl. 17, fig. 1). Each has a broad, more or less concave frontal limb and margin marked by radiating ridges, large eyes, and an elongate glabella marked by five short lobes on each side.

The pygidium in each species is of the same type and the surface has the same punctate character in each.

Anomocare convexa is associated with several other species of Anomocare.

Formation an locality.—Middle Cambrian: (90x) Conasauga formation; in and attached to the outer surface of siliceous nodules in argillaceous shales, Coosa Valley, east of Center, Cherokee County, Alabama.

Collected by A. M. Gibson, 1884; and Cooper Curtice, 1885.

This species is represented by specimens of the cranidium and associated pygidia that are referred to it. It is closely related to Anomocare flava Walcott. It differs in details of frontal limb and border, glabella, and fixed cheeks. It has a less deeply impressed line between the frontal limb and border than that of A. flava.

Formation and locality.—Middle Cambrian: (35r) Fu-chóu series; limestones near the base of the series just above the white quartzite, collected in a low bluff on the shore of Tschang-hsing-tau island, east of Niang-niang-kung, Liau-tung, Manchuria, China.

Collected by J. P. Iddings and Li San.

This fine species is represented by numerous specimens of fragments of the cephalon, segments of the thorax, and entire pygidia. They are all compressed in a fine, argillaceous shale and usually only a faint impression remains. The cranidium is not unlike that of