316 



pair of oblique furrows (occasionally others indistinctly 

 visible); strong, bifurcating occipital furrow: lunate eyes: 

 granulose thorax; abruptly deflected pleurae; semi-elliptical, 

 well-grooved pygidium, with strong border. 

 Found in the Encrinal limestone, at Section 5 (very rare). 

 Proetus rowl (Green.) (Fig. 260.) (Pal. X. Y., Vol. 

 VII., p. 119, Pis. XXL, XXIII.) 

 Distinguishing ( 'haracters — Semi-elliptical to semi-circular 



cephalon: broad flat border; genal 

 spines reaching to fourth thoracic seg- 

 ment: simple, elongate sub-conate gla- 

 bella, sloping to a broadly rounded an- 

 terior extremity; lateral furrows absent ; 

 large lunate eyes; axis occupying more 

 than one-third the width of the thorax : 

 pleurae with grooves; pygidium with 

 nine or ten low, flattened annulations 

 in the axis, and six in the lateral lobes, 

 with indications of a seventh ; con- 

 spicuously thickened border; smooth 

 or faintly pustulose surfaces. 

 Found at 'Hamburg and Eighteen Mile Creek, Erie 

 County " ( Hall ). Found in the Trilobite (? ) beds, at Section 

 8 (E. P. Johnson). 



Proetus curvimarginatus. Hall. (?) (Fig. 261.) 

 (Proetus sp. Grabau : Faunas Ham. Group, p. 242. Com- 

 pare Pal. X. Y.. Vol. VII., p. 94, PI. XXII.) 



D is tingu is h in g ( 'haracters.— Sub-triangular glabella , 

 rounded anteriorly; three pair glabellar furrows, the last 



pair curving strongly backwards and 

 reaching the occipital furrow, the two 

 anterior pair somewhat less curving, and 

 shorter. Surface strongly pustulose. The 

 specimen here described and figured re- 

 tains only the glabella, which has the out- 

 line and pustulose character of P. curvi- 

 marginatus from Pendleton, Indiana. 



Fig. 260. Proetus rowi. 

 Outline of a small individ- 

 ual, enlarged to two 

 diameters (after Hall and 

 Clarke). 



Fig. 261. Profit us 

 curvimarginatus. (?) 

 'ih.- glabella, x \\&. 

 Pleurodietyum beds, 

 Wanakah Cliff. (Origi- 

 nal.) 



