34 PBOCEEDINGS OF THE NATIONAL MUSEUM vol. 76 



much larger spine. Unfortunately the posterior extremity of the 

 pygidium is missing, so that its characters remain unknown. The 

 uncommonly wide pleural lobes are covered with very fine striae 

 paralleling the outer edge. 



Occurrence. — Whitesburg limestone, near Albany, Tennessee, where 

 it is associated with more numerous specimens of T. hipunctatus. 

 Also at Pratts Ferry, Alabama. 



Gotypes.—C2it. No. 80544, U.S.N.M. 



TELEPHUS PRATTENSIS, new species 



Plate 3, Figures 16-19 



Associated with typical specimens of T. hipimctatus a single small 

 but good cranidium was found in 1910 at Pratts Ferry, Alabama, 

 that departs in important respects from the usual characters of 

 that species. Since then three other but structurally precisely simi- 

 lar cranidia were found in the lower 50 feet of the typical section 

 of the Whitesburg limestone in Tennessee. In certain of their fea- 

 tures these specimens approach the three Tellico sandstone species 

 of the genus without, however, agreeing exactly with any of them. 

 For convenience of reference it is thought advisable to give them 

 another name, leaving to the future the decision as to its final and 

 true systematic position. 



Compared with T. hipunctatus it is distinguished at once by the 

 very slight depth or complete obsolescence of the glabellar pits and 

 absence of any indication of the posterior pair of lobes. Otherwise 

 the glabella is nearly the same as in T. hipunctatus, particularly 

 in the matters of outline and general convexity. Comparing other 

 features, however, it is found that the lateral parts of the palpebral 

 band are wider whereas the anterior spines are relatively smaller 

 and less widely separated, the antero-lateral parts of the outline 

 of the cranidium are more rounded, the convex areas of the fixed 

 cheeks are smaller and much narrower anteriorly, and the occipital 

 furrow straighter than in T. hipunctatus. These differences impart 

 an aspect to the cranidium sufficiently distinctive to convince one 

 that entire specimens of these trilobites would show equally important 

 peculiarities in the unknown parts. 



A closer relative perhaps is T. iriipunctatus, in which the glabella 

 may be said to be precisely similar in form and surface markings. 

 The present species, however, has a much smaller occipital spine, 

 the anterior part of the outline of the cranidium more rounded, 

 and the fixed cheeks decidedly smaller. The last character dis- 

 tinguishes T. prattensis from all of the Whitesburg and Tellico 

 species. 



