PALEONTOLOGY OF NEW YORK. 



lobes being coalesced, anil the first and third pairs of farrows uniting to form 

 a single pair of longitudinal furrows which extend in a broad curve from the 

 anterior margin to the occipital furrow. Third glabellar lobes obsolete. 

 Lateral lobes elongate, bounded on the sides by sigmoid curves, and sepa- 

 rated from the frontal lobe, the eye-lobe and the margin by furrows of equal 

 strength. 



Facial Sutures normal. Eye-lobe slightly depressed. Fixed portions of the 

 cheeks short, abruptly deflected to the occipital furrow. Free portions of 

 the cheeks and the occipital ring not observed. Border narrow, thickened; 

 marginal sulcus strong. 



Surface evep.lv covered by fine closely crowded tubercles, which are 

 strongest upon the posterior portion of the frontal lobe; not, however, 

 becoming spiniform. 



An htpostoma found in association with this head is sub-quadrate in outline, 

 convex on the anterior margin, broadly emarginate behind, the postero-lateral 

 area- being broad and rounded. The centrum is small, sub-hemispherical, 

 distinctly defined in front and at the sides, merging behind into the elevated 

 median area. The longitudinal furrows are broad and deep and from these 

 two pairs of obscure, oblique sulci pass inward over the median area, leaving 

 between them a pair of inconspicuous nodes just behind the centrum. The 

 margins near the anterolateral angles are strongly elevated. The surface 

 of the centrum is covered with fine tubercles. 



Dimensions. The single cephalon observed measures 16 mm. in length and 

 25 nun. in width at the occipital furrow. The length of the hypostoma is 9 

 mm.; its width 16 mm. 



Observations: The sub-genus Hoplolichas, Dames, includes a series of Silurian 

 species {Lichas trtcuspidatus, Beyrich ; L. proboscideus, Dames; L. conico-fuber- 

 culatas, Nieszkowski; J.. Plautini, Schmidt; L. longispina, Schmidt; L. furcifer, 



imidt), with which this fossil agrees in the form and contour of the head, 

 especially of the frontal lobe. This lobe is more clavate, never so elevated or 



