PLATE XXII. 

 Proetus angustefrons. 



Page 9] 

 See Plate 20. 

 Fig. 1. The intra-sutural portion of the cephalon, retaining the crust, showing the form of the glabella, 

 the sloping frontal border and preserving indications of three pail's of lateral farrows. Enlarged 

 in two diameters. 



Schoharie grit. Schoharie, Schoharie county. 

 Pig. .'. Tlit* movable cheeks, preserving the visual surfaces of the eyes, showing the character of the gena) 

 spines and the direction of the suture upon the frontal doublure. Enlarged to two diameters. 

 Schoharie grit. Near Gla/rksmlle, Albany county. 

 Fig. :i. A small pygidium showing the distinctly sulcate and finelj tubercled annulations, and the broad, 

 smooth border. Enlarged to two diameters. 



Schoharie grit. Near Clarlssville, Albany county. 



PliOETI 8 < lONKADI. 



Page B9 



See Plates 20 and 21. 



I i- 4. A pygidium, showing the general convexitj and the sloping borders. The lateral annulations, 



which are usually quite indistinct in this species, have been given too much prominence in the 



drawing. Enlarged to two diameters. 



Schoharie grit. Schoharie, Schoharie county. 



Proetus, sp. 



Page 94. 

 Fig. 5. An imperfect cephalon retaining a portion of the crust and showing a more convex glabella and a 

 broader and flatter border than in either of the foregoing species. Enlarged to two diameters. 

 Schoharie grit. Schoharie, Schoharie county. 

 Fig. ti. An internal cast of a pygidium which differs from that of the preceding species in the fewer annu- 

 lations. Enlarged to two diameters 



Schoharie grit. Knox, Albany county. 



Proetus latimaroinatus. 



Page !)7. 

 Fig. 7. A large glabella, natural size, showing the lateral furrows and the broad, Hat frontal bonier. 



Schoharie grit. Pendleton, Indiana. 

 Fig. 8. The left movable cheek referred to this species. 



Schoharie grit. Pendleton, Indiana. 

 Fig. 9. The right movable cheek. 



Schoharie grit. Pendleton, Indiana. 

 Fig. 10. A very imperfect individual, indicating the form and proportions of the body. 



Schoharie grit. Pendleton, Indiana. 

 Fig. II. The pygidium, showing the essential characters of this part of the body. 



Schoharie grit. Pendleton, Indiana. 

 Fig. 12. The pygidium and a portion of the thorax of a large individual. 



Schoharie grit Pendleton, Indiana. 



Proetus curvimarginatus. 



Page 94. 

 Fig. 13. A somewhat imperfect example, retaining a portion of the crust and showing the relative pro- 

 portions of the species. 



Schoharie grit, Pendleton, Indiana. 

 Fig. 14. The intra-sutural portion of a cephalon, showing the conate form of the glabella, the recurved 



frontal border and the four pairs and the .accessory pair of lateral furrows. 

 Fig. 15. Outline profile of the same, showing- the elevation of the glabella and the curvature of the bonier. 



Schoharie grit. Pendleton, Indiana. 

 Fig. lti. A smaller, imperfect individual drawn from a gutta-percha impression from a natural mould of the 

 internal surface in the sandstone. 



Schoharie grit. Pendleton, Indiana. 

 Fig'. 17. A small pygidium. showing the character of the annulations and the curvature of the border. 

 Schoharie grit. Pendleton, Indiana. 



