PLATE XIX b. 



LlCHAS (HOPLOLICHAS) in I. I 1 8. 

 Page SI. 

 See Plate 25. 

 Fig. 1. An imperfect eephalon. wanting the movable cheeks and the occipital ring, but showing the char- 

 acter of the glabellar lobes. 

 Fig. 2. Profile of the same, showing the elevation of the frontal and lateral glabellar lobes. 

 Upper Helderberg limestone. Pmrinii of Ontario. 



Lichas (Arges) contusus. 



Page 83. 

 Fig. 3. A eephalon, wanting the movable cheeks; showing the elongate frontal lube, the short and broad 

 lateral lobes, and the relatively broad genal areas. The original is a cast of the internal 

 surface, which makes the cephalic furrows appear broader and deeper than when the crust is 

 retained. Enlarged to two diameters. 



Corniferous limestone. Canandoiyua. Ontario county. 

 Fig. 4. A eephalon, wanting the movable cheeks, but retaining a portion of the crust. 

 Fig. 5 The same, enlarged to two diameters. 



Fig. 6. The same in profile, enlarged to two diameters, showing the regular convexity of the frontal lobe, 

 its elevation above the lateral lobes for its entire length, the convexity of the genal area, and 

 the elevation of the occipital ring. 



Corniferous limestone. Near ClarJciVille, Albany county. 



Lichas (Ceratolichas) gryps. 



Page W. 

 Pig, 7. The intra-sutural portion of a eephalon, retaining the crust and showing the gently undulate 

 frontal border, the short, abruptly elevated frontal lobe, the depressed lateral lobes, and also 

 the bases of two spines on the frontal lobe : of one spine on each cheek just within the eye- 

 node, and a single long recurved and slightly incurved spine on the occipital ring, accompanied 

 by the base of a second, the latter spine being restored in outline. Enlarged to two diameters. 

 Fig. 8. A profile of the same similarly enlarged, the broken spines being restored in outline. 



Corniferous limestone. Schoharie. Schoharie county. 

 Fig. 9. A small eephalon, showing the bases of the three pairs of spines. The specimen is inclined forward 

 somewhat more than in the drawing of tig. 7, foreshortening the frontal lobe. The original is 

 an internal cast in decomposed chert. Enlarged to three diameters. 

 Fig. 10. The same, in profile. 

 Fig. 1 1 . The same, viewed from the front. 



Corniferous limestone. Canandaigua, Ontario county. 

 Fig. 12. A fragment of the middle lobe of the glabella, showing the length and character of its spines. 

 Fig. 12a. The same, enlarged to two diameters. 



Fig. 13. The same, similarly enlarged and viewed in profile, showing the length and curvature of the gla- 

 bellar spines. 



Corniferous limestone. Ciiiiiimloiyua. Ontario minify. 



