PLATE XVII. 



Lichas (Terataspis) gkandis. 



Page 73. 

 See Plates 18 and 19. 

 Fig. 1. Profile of the cephalon represented on plate 18, showing- the elevation of the glabella and one of 

 the glabellar spines; the occipital ring, and the constriction about the base of the frontal lobe. 

 Upper Helderberg limestone. Cayuga, Prouim t of Ontario. 

 Fig. 2. Dorsal view of a much w< athered specimen of the cephalon, wanting the free cheeks. 

 Fig. 3. Profile of the same. 



Schoharie grit. Schoharie, Schoharie county. 

 Fig. 4. Tho posterior portion of a large cephalon, showing the prominent lateral lobes and bases of the 

 double glabellar spines, and the broad occipital ring with the clavate processes upon its posterior 

 margin. The base of a strong spine lying just within the palpebral furrow, which is shown in 

 the specimen, is not represented in the figure. 

 Fig. 5. The same viewed from behind, showing tin- elevation of the lateral lobes and of the processes 

 upon the occipital ring. 



Schoharie grit. Schoharie, Schoharie county. 

 Pig. 6. An imperfect pygidium, showing the pleural annulations and a portion of the marginal spines. 

 Schoharie grit. Schoharie, county. 



