Pro/. E. W. Claypole — On a New Carboniferous Trilohite. 305 



characters distinguishing these groups seem not to have been very 

 clearly pointed out." (Proc. Acad. Nat. Sci. Phil., 1865, p. 267-8.) 



The pygidium of Proetiis auriculatiis, Hall, is not certainly known. 

 That which is supposed to belong to this species is " naarked by 

 seven or eight ribs terminating in a wide spreading border." (15th 

 Eeport on State Cabinet of New York, 1862, p. 107.) 



In Proetus Verneuili, as figured by Prof. Hall in his Illustrations 

 of Devonian Fossils (pt. xv. fig. 18), the lateral ribs extend partly 

 across the border, forming a line of marginal tubercles, but there is 

 no crenation of the edge. This is the nearest approach to the 

 appearance described by Prof. Meek {loc. cit.), with which I am 

 acquainted. 



A. Dalmanites ? Cuyahogae, s.n. x 2. B. Phillipsia Lodioisis, Meek, x 2. 



1. Griffithides globiceps, De Kon. 2. Phillipsia Berbiensis, Mart. 



3. Brachymetopus discors, M'Coy. 



It follows, therefore, that with the single possible exception of 

 Phillipsia Lodiensis, as described by Prof. Meek, no Trilobite has 

 been announced from the American Carboniferous rocks in which the 

 pleural ridges of the pygidium extend beyond the border. The 

 occurrence, therefore, of the form figured and described above is of 

 considerable interest to palaeontologists. It was found in the Cuya- 

 hoga Shale, the uppermost member of the Lower Carboniferous 

 system in Northern Ohio, and its description so far as the specimen 

 allows is as follows : — 



DECADE III. — VOL. I. — NO. VII. 20 



