22 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 76 



made and mainly relied on by Hadding in preparing the drawings 

 published by him. 



The mainly distinctive features of the cranidium of T . ameHcanus 

 are the rather strong convexity and semiovate outline of the glabella, 

 the small size and weak development of its surface tuberculation, the 

 small anterior width and crescentic form of the fixed cheeks and the 

 resulting general roundness of the lateral and anterior parts of 

 the outline, and the relative narrowness of the occipital ring and 

 the reduction of its spine to a minute elongate medially located node. 

 Its nearest ally seems to be T. mystlcensis, which, however, lacks the 

 surface tuberculation, has somewhat wider and more crescent-shaped 

 occipital ring, less evenly convex glabella, less sharply ridged fixed 

 cheeks, and apparently more delicate anterior denticles. The nearest 

 of the southern Appalachian species is T. prattensis, but the wavy 

 and anastomosing longitudinal lines on its glabella and fixed cheeks, 

 instead of pustules, render confusion in this case unlikely. 



Occurrence. — Newfoundland, Division N and P, which probably 

 locates the species stratigraphically somewhere within the span cov- 

 ered in the southern Appalachian region by the Blount group. 



TELEPHUS MYSTICENSIS, new species and SIMULATOR, new variety 

 Plate 6, Figures 1-7 



The surface of the glabella and fixed cheeks in both the typical 

 form of the species and its variety seems entirely without tubercles, 

 and if the occipital ring has a median tubercle or spine it must be 

 very small. The shape and contour of the glabella is essentially as 

 in T. fractus and T. amencanus except that its middle third is 

 flanked on each side by a shallow curved depression and the occipital 

 ring is wider in the middle and more crescentic in outline. The out- 

 line of the sides and front of the cranidium in the holotype is round- 

 ed about as in T. amencanus., but the part that lies in front of the 

 middle third of the glabella is more prominent and distinctly in- 

 curved in front and the inner pair of the four frontal spines rela- 

 tively small and so strongly curved downward that only the bases 

 of these spines are visible in a dorsal view. The outer pair, how- 

 ever, is distinctly visible in such views. The fixed cheeks are as 

 narrow as in T. aviericaiius., but the convex area is longer, extend- 

 ing forward as a diminishing low ridge almost as far as the anterior 

 extremity of the glabella. Excepting T. aviericanus the present 

 species differs from all the other species of the genus in the approxi- 

 mately semicircular outline of its cranidium, in the general narrow- 

 ness of its fixed cheeks, and in the fact that the convex areas of these 

 cheeks are widest posteriorly instead of anteriorly and the outer pair 



