Page:Cincinnati Quart. J. Sci. 2 347-349.djvu/3

Rh by a semi-circular depression into two short abruptly attenuate points, obliquely striated from the medial line backwards.

Surface. Glabella finely tuberculated. Movable cheeks very finely granulated. Axial lobe smooth with a few fine punctures. Outer spines of the head, pleuræ, (outer and inner surface), and pygidium striated.

Formation and locality. Upper third of the Trenton Limestone, Trenton Falls, N. Y. The glabella of this species closely resembles the glabella described by Prof. E. Billings as Remopleurides Canadensis, from the Chazy Limestone. Differs in the narrow palpebral lobes and glabellar furrows.

Cephalic shield, irregular, rough, tuberculated and spinous. An outline of the margin would be represented by a depressed arc in front, a slightly longer digitated and expanded arc for each cheek, and a still longer arc for each of the projecting spines, while a half ellipse would be formed between the projecting spine from the occipital part of the glabella and each of the cheek spines. The cheeks have about twelve or fourteen digitations or short curved spines on the lateral margins, and about twenty prominent tubercles on the face of each, with their posterior extremities produced, in a strong, round, oblique, curving spine covered with numerous smaller tubercles or asperities. The eyes are prominent, directed backwards, and situated near the posterior junction of the cheeks with the glabella. The glabella is somewhat anchor shaped in outline; the middle lobe has an expanded elevation