WHiTFAVEs] DEVONIAN FOSSILS OF MANTTORA, ETC 353 



FISHES. 



HOLOCEPHALl. 



(:HIM.ER0I])KT. 



Ptyctodus calcholus, Ncwherry and Worthen. 



I'iiiiiilas ralreolwi, Newlicrvy and Woithcii. ISCid. Pal. Illinois, vol. II, p. 100, pi. x, 

 ti^s. 10, 1(1 a-u. 



P/t/rfo(lus<-a/'ro/n,^^ Xowheny. 1S7."). Rep. (ieol. Sm-\'. Ohio, \-ol. II, pt. 2, (Pala-onl.) 

 l>. 59, pi. lix, tig. V.l 



Lake WinuijM'gosis, on a small island at the southern extremity of the 

 lake (one tooth), im the western shore of Dawson Bay, at Point Wilkins 

 (three separate teeth), and at the head of a small hay about three miles 

 .south of that point (one tooth); J. B. Tyi-rell, 1889. Two small teeth, 

 which are possibly referable to this speoie.s, were obtained by Mr. Tyrrell, 

 in 1889, at an exposui-e on the Red Deer River, about a mile aVjove the 

 Lower Salt Spring. 



Separate teeth of /•". calfcol ihs are not uncommon in the Hamilton 

 Formation of Wcstein < )ntario, on the banks of the Sable River, at 

 Bartlett's Mills, near Arkona, and idsewhere. 



Rhvnohodus. (Sp. Undt.) 



An imperfect tooth, apparently from the lower jaw, of a species of 

 Rliynrlidilas, was collected by Profe.ssoi- H. Youle Hind, in 1858, at the 

 north end of Manitoba Island. The specimen is still pi-eserved in tlie 

 museuu] of the Survey. 



DIPNOI. 



ARTHR(.)I)IRA. 



DiNiciiTins Canadensis. (N. Sp.) 



Plate 46, fig. Pi. 



" Premaxillary " tooth oi' dental plate (the only part of the fish 

 yet collected) of small size for the genu.s, its upper portion Literally 

 expanded and subrhombic in outline, its lower portion aVji'uptly con- 

 tracted on one side and produced into a large, narrow, conical and 

 pointed process which projects downwai-d and constitutes ;<. lateral cone 

 of the crown. Up[>er and expanded portion of the tooth convex 

 externally and concave internally : the angle formed by its upper and 



