PLATE XVIII. 
Lichas (Teuataspis) grandis. 
See Plates 17 and 19. 
Fig-. 1. Dorsal vie-w of a vei-y large cephalon wanting the movable cheeks, showing the double spines on 
the lateral lobes, and the very bi-oad occipital ring, with the clavate processes upon the posterior 
margin i-estored in outline. The specimen shows the base of a strong spine situated just within 
the palpebral furrow, but this is not i-epresented in the drawing. 
Fig. 2. The same viewed from behind, showing the elevation of the frontal and lateral lobes. 
Upper Helderberg gi-oup. Cayuga, Province of Ontario. 
