May, 1919] Silurian Fossils From Ohio 393 



Calymene whittakeri Sp. nov. 

 Plate XIX, Figs. 9 A, B. 



Anterior margin of the cephalon project in front of the glabella 

 in the form of a lip; in the type specimen, for a distance of 3 millimeters. 

 Compared with typical Calymene senaria Conrad, from the Trenton 

 of New York, the lip is less elongate and not so nasute; the genal angles 

 are rounded; the surface distinctly granulated, the granules being some- 

 what coarser than in most species of Calymene. The distinctive feature, 

 however, which is regarded as most characteristic of the species, is 

 presented by the pygidium. Here the ribs curve strongly toward the 

 rear so as to become sub-parallel on the posterior half of the pygidium. 

 All of the ribs extend to within a short distance of the margin of the 

 pygidium, and the first four ribs are distinctly furrowed along their 

 entire length. The fifth rib may be furrowed but in that case its inner 

 margin is not limited from the median part of the p3^gidium posteriorly. 



At Fields, about half way betw^een CoUingwood and Meaford, 

 on the southern shore of Georgian Bay, in Ontario, the species 

 of Calymene here descibed occurs in the CoUingwood forma- 

 tion, as exposed on the shore of the bay. It is named in 

 honor of Dr. E. J. Whittaker, of the Geological Survey of 

 Canada, in memory of pleasant days spent together in un- 

 ravelling the geology of Georgian Bay and Manitoulin island. 



Calymene cf. vogdesi Foerste. 

 Plate XVIII, Fig. 6; Plate XTX, Fig. 3. 



In the Flolophragma zone, at the top of the Upper or Lilley 

 member of the West Union formation, in the Zink or Corpora- 

 tion quarry, within the eastern limits of Hillsboro, Ohio, a 

 Calymene is found which, among described species, most 

 nearly resembles Calymene vogdesi, a. typical Brassfield species. 



In the specimen figured, the anterior rim of the cephalon projects 

 2.5 mm. be^^ond the anterior margin of the glabella. The anterior 

 rim forms an angle of from 155 to 145 degrees with the general surface 

 of the base of the cephalon. Compared with typical Calymene voidest 

 (Plate XIX, Fig. 5), the furrow immediateh' anterior to the glabella 

 is not as deep; the median part of the glabella, between the lobes, is 

 narrower; the anterior half of the glabella, in front of the second pair 

 of glabellar lobes, is somewhat longer and more quadratic, retaining 

 its width as far as the groove outlining the anterior margin of the 

 glabella. No well preserved pygidia are at hand. In typical Calymene 

 vogdesi the pleural ribs extend almost as far as the margin of the 

 pygidium; while in some specimens the ribs are faintly grooved along 

 their entire length, in others the grooving is distinct only near the dorsal 

 furrow and again toward the distal parts of the ribs, or the grooving 

 may be confined practically to the proximal parts of the ribs, near 

 the dorsal furrow. 



