24 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 68 



on comparison of the figures. One of the specimens shows minute 

 fluting on the underside of the bar. 



Occurrence. — Devonian (Rhinestreet) : Shaleton, N. Y. 



Cotypes.—C^it. No. 11265, U.S.N.M. 



BRYANTODUS NITIDUS, new species 



Plate 4, figs. 12-14 



This neat species as based upon Figures 12 and 13 is characterized 

 by the rather strong even curvature of the bar, prominence although 

 not great size of the main cusp, numerous, subequal, outwardly 

 diminishing denticles all inclined toward the posterior end and the 

 small size of the protuberance on the under side of the bar imme- 

 diately beneath the main cusp. Both specimens have 13 denticles 

 behind and about 10 in front of the main cusp. Figure 14 repre- 

 sents a specimen referred here with doubt for reasons apparent 

 upon inspection of the photograph. This species belongs to a group 

 better developed in the Mississippian black shales. 



Occurrence. — Devonian (Rhinestreet) : Shaleton, N. Y. 



C oty pes.— C^i. No. 1126G, U.S.N.M. 



BRYANTODUS CONJUNCTUS, new species 



Plate 4, figs. 8, 9 



Curvature of bar uncommonly strong. Main cusp of moderate 

 size, sharp edged but apparently terminating bluntly, with 10 or 11 

 flat, convex coalescent denticles on each side. 



The strong curvature of the bar and the rather short and not 

 large main cusp with an equal number of numerous denticles on 

 each side will sufficiently distinguish this species which, however, is 

 not to be counted as a typical species of the genus. 



Occurrence. — Devonian (Rhinestreet) : Shaleton, N. Y. 



Cotypes.—Q2Li. No. 11267, U.S.N.M. 



BRYANTODUS SEMISEPARATUS. new species 



Plate 4, fig. 16 



Bar rather strongly curved, main cusp slender, very long coalesc- 

 ing with the shorter denticle immediately in front, and this with all 

 the others to the anterior extremity. Posterior denticles long, 

 slender, seven in number, and all separate. 



Occurrence. — Devonian (Rhinestreet) : Shaleton, N. Y. 



Uolotype.—Q^X. No. 11268, U.S.N.M. 



BRYANTODUS NORMALIS, new species 



Plate 4, figs. 25, 26, and 27 



Allied to B. crassidens., B. obliquus, and B. sinuatus but more par- 

 ticularly to the first from which it differs in having both the lateral 



