AND DEVONIAN CONODONTS. 365 
Potyenatuus princers, Hinde. (PI. XVI. fig. 23.) 
On a narrow, elongated base there is a scries of eleven relatively 
large and robust teeth, somewhat oval in section. The central teeth 
are larger than those near the extremities of the base. Length of 
base 2 lines, of the largest tooth 3line. Centrodus simplex, Pander 
(‘ Monographie,’ p. 31, tab. 24. fig. 3), seems to be a fragment of a 
similarly large tooth from the Carboniferous of Russia. 
Loc. North Evans, New York: from the “* Conodont-bed ” of the 
Hamilton group and the Genesee Shale. 
Potyenaruus coronatus, Hinde. (Pl. XVII. fig. 1.) 
Base very narrow and gracefully arched, with seven subequal, 
relatively large, robust, curved teeth. The teeth in this form are of 
an ivory-white, whilst the base is brownish and translucent. It is 
closely allied to Centrodus convexus, Pander (‘ Monographie,’ p. 31, 
tab. 24. fig. 4); but has a narrower base, more teeth, and no inter- 
ealated small ones. Length of base ? line, of the longest tooth 
= line. 
Loc. Kettle Point, and in erratic boulders on north shore of Lake 
Erie, Ontario: Genesee Shale. 
Potyenatuus soripus, Hinde. (PI. XVII. fig. 2.) 
On a short, very thick, and wide base there is a closely arranged 
series, varying from seven to eleven in number, of subequal, short, 
stout and obtuse teeth. Very abundant. 
Loc. North Evans, New York: from the ‘‘ Conodont-bed ” of the 
Hamilton group. 
Potyenatuus crassus, Hinde. (Pl. XVII. fig. 3.) 
Base of tooth narrow, curved, and relatively very thick, with a 
prominent ridge, in which are six obtuse teeth or crenulations ; the 
posterior extremity crest-like, with two stout teeth on the summit. 
Length 3 line. 
This form is allied to the crested teeth of P. dubius; but it is a 
shorter and more robust form. 
Loc. North Evans, New York: “ Conodont-bed ” of the Hamilton 
eroup. 
Poryenatuus? serratus, Hinde. (PI. XVII. figs. 4 & 5). 
Tooth or jaw formed of a thin, curved, and highly convex basal 
plate, truncated at one end, and with a blunt projection at the 
opposite extremity. On the upper edge are about thirty minute 
crenulations or blunted teeth. Length 1 line, width 3 line. 
This species and the two following differ from the more typical 
forms of Conodonts ; but as they appear to be connected with the 
* crested” teeth of P. dubius, I place them provisionally under that 
genus. They have also a resemblance to G'nathodus mosquensis, 
Pander (‘ Monographie,’ p. 33, tab. 2. figs. 10 a, b,c). P.? serratus 
appears at present only in one place, where, however, it is abundant. 
Loc. Kettle Point, Ontario; Genesee Shale. 
