OF DENISON UNIVERSITY. Uo 



at Trenton Falls, New York. The sides of the middle lobe of the 

 glabella are but very slightly divergent posteriorly, reaching the occip- 

 ital ring without any change of direction, therefore not forming a pestle 

 shaped widening at the posterior end of this lobe. The lateral 

 lobes also reach the occipital furrow, their sides preserving the same 

 degree of curvature behind the palpebral lobes until they reach the 

 occipital furrow. The facial sutures extend from the palpebral lobe 

 with a short curve laterally and posteriorly to the posterior margin of 

 the head. The fixed cheeks occupy all of that portion of the head 

 which lies between the facial sutures, the palpebral lobes, and the lat- 

 eral lobes of the glabella. Beginning near the posterior termination 

 of the facial suture, a furrow, narrow but distinct, runs with a mod- 

 erate curvature along the movable cheek forwards, within a moderate 

 distance from the eye. 



'i'he Ohio specimens we propose to name Lichas Halli :\{\qx the 

 illustrious state geologist of New York. The sides of the middle lobe 

 of the glabella at a short distance from the occipital furrow make a 

 rapid double curve laterally, then incurve slightly until they reach the 

 occipital furrow, giving by this means to the posterior end of the mid- 

 dle lobe of the glabella a shape somewhat like that of an apothecary's 

 pestle, and which is characteristic of quite a distinct section of the 

 genus Lichas. The sides of the lateral lobes of the glabella converge 

 posteriorly and meet near the lateral edges of the pestle-like forma- 

 tion just described, but do not extend to the occipital furrow. Be- 

 tween the postero-lateral terminations of the lateral lobes, the lateral 

 portions of the pestle-like termination of the middle lobes, the occi- 

 pital furrow, and the fixed cheeks lie very marked lobes, which from 

 their proximity to the occipital furrow may be called occipital lobes. 

 In consequence of these lobes the inner posterior edge of the fixed 

 cheeks is considerably incurved. The glabella as a whole is rather 

 flattened above but anteriorly it curves rather rapidly down to the an- 

 terior margin of the head. The pali)el)ral lobes are rather large. 

 There seems to be no distinct furrow on the movable cheeks running 

 from the anterior to the posterior sides of the same. The interpreta- 

 tion of the structure of the cheeks is not so clear from the specimens 

 at hand but seem to follow some of the more familiar types. The ix)s- 

 terior margin of the fixed cheeks namely curve forward, joins the pos- 

 terior margin of the movable cheeks, the latter curving backward and 

 forming with the anterior edge of the movable cheeks a broad pleura- 



