152 CATALOG OP FOSSIL FISHES IN THE MUSEUM 



but unlike any other known to us, and we describe it here as a new 

 genus. 



E 2575 Type.—K large dental plate (PL 55, fig. 3). 



Formation and Locality. — Conodont bed (Lower Genesee) ; Eighteen 

 Mile Creek, near North Evans, Erie County, N. Y. Collected by W. 

 L. Bryant. 



Fig. 53. Acmoniodus clarkei, n. gen., n. sp. Outline of Type Specimen to 



Show Form of the Anterior and Posterior Tritors. (See PI. 55, 



Fig. 3.) Xf. E 2575 



A large, symmetrical dental plate, having the outline shown in 

 figure 53 ; with two tritors in the median line, one at the anterior, or 

 front end of the plate, the other occupying the posterior third of the 

 element. Anterior tritor elliptical in outHne, with the long diameter 

 in the antero-posterior line of the element; not demarcated from rest 

 of plate but merging gently into it; its upper surface covered with a 

 shining, enamel-hke substance and worn by use. On either side of 

 posterior half of front tritor, a shallow depression in the bone, appar- 

 ently produced by an upper apposing tritor. Posterior tritor shaped 

 like the median-occipital of a dinichtbyid, its anterior margin exca- 



