CRUSTACEA. 73 



LICII AD.h. 



L ICH AS, Dalman. 1826. 



[s.-g.] T Eli AT ASP IS, Hall. 18G3. 

 Lichas (Terataspis) grandis. 



PLATE XVII, FIGS. 1-6; PLATE XVIII, FIGS. 1,2; PLATE \l.\. FIGS. 1 7. 



Lichas grandis. Hall. Descriptions New Species of Fossils, etc., p. 82. 1861. 



Lichas grandis, Hall. Fifteenth Rept. N. Y. State Cab. Nat. Ili-i . p. Hi) 1862. 



Lichas grandis, sub-genus? Terataspis, Hall. Sixteenth Rept. N. Y. Stat.- Cab. Nat. lli.^t.. p. 223. 1863. 



Lichas superbus, Billings. Canadian Naturalist and Geologist, vol. vii, IV:'. -1. p. 239. 1875. 



Acidaspis (Terataspis) grandis. Hall. Illustrations of Devonian Fossils, pis. xvii. xviii. lsTD. 



Cephalon very prominent in front, abruptly depressed behind ; length to width 

 between the eyes as 5 to 4 ; to greatest width as 5 to 7. Frontal border 

 broad, flat and sloping outward; margin not thickened. 



The facial sutures begin on the posterior margin a short distance outside 

 the axial furrows, and slope obliquely forward, curving abruptly and passing 

 thence directly inward to the eye; thence directed outward in a broad curve 

 to the anterior margin. 



Glabella sub-quadrate in general outline; anterior lobe ovoid or ellipsoid, 

 extremely prominent, tumid, evenly convex and strongly constricted about 

 the base; length ecpial to five-eighths the length of the glabella; length to 

 width as 6 to 5. Longitudinal furrows very broad and deep, merging at t he 

 posterior margin of the frontal lobe, and forming a broad, median depression, 

 which narrows for a short distance and widens thence to the occipital ring. 

 The two lateral lobes are broad, directed posteriorly, and at the summit each 

 one is produced into a conspicuous compound spine, the inner branch of which 

 is the longer, reaching beyond the height of the anterior lobe, and projecting 

 over the occipital ring. These lateral lobes may be regarded as the coalesced 

 first and second pairs, the third pair being obsolete or indicated only by a 

 faint elevation of the crust near the occipital ring, crowned by a few strong 



