364 G. J. HINDE ON CAMBRO-SILURIAN 
plates present. Whatever the animal may have been, it appears to 
have had a very wide distribution both in Devonian and Carboni- 
ferous times. 
Locality and Formation. The single specimen, in which the above- 
mentioned teeth and plates are shown together, is from the Genesee 
Shale (Devonian) at North Evans, N.Y. 
PoLyenataus pupticatus, Hinde. (Pl. XVI. fig. 19.) 
Base of the compound tooth bent at an obtuse angle, narrow, and 
slightly convex ; in the centre a needle-like tooth oblique to the base, 
with a similar but slightly shorter tooth adjacent to it; this is followed 
by six acute denticles on one side of the base, and on the opposite 
side are eleven very small denticles nearly at right angles to the 
base. Length of base 3 line. 
This form is closely allied to some of the pectinate teeth of P. 
dubius and may belong to a mere variety of that species. The de- 
tached position of this and the forms described below makes it a 
necessity to place them under different names, though there is great 
probability that they do not belong to more than one or two species. 
Loc, Bear Creek, Ontario: Genesee Shale. 
PoLyenatuus Rapiatus, Hinde. (PI. XVI. fig. 20.) 
Tooth very minute ; the base curved, narrow, and compressed in 
the centre ; a broad, slightly convex, main tooth inclined to the base; 
on one side of this there are six, and on the other four flattened, 
curved denticles. Length of base 3 line. 
Loc. Kettle Point, Ontario: Genesee Shale. 
PoLyenaTHus IMMERSUS, Hinde. (PI. XVI. fig. 21.) 
Tooth minute; base slightly curved and very wide; nearly in the 
centre 1s a short, blunted, main tooth, on one side of which there 
are ten, and on the other eight very delicate, elongated denticles. 
All these teeth are so deeply imbedded in the delicate transparent 
base that only the tips project beyond it. Length of base 3 line, of 
- the main tooth 7 line. 
This form closely resembles Cienog gnathus Verneuilli, Pander, frotn 
the Devonian of Russia (‘ Monographie,’ p. 32, tab. Qa, fig. 16). 
Loc. Kettle Point, and in erratic boulders on the north “ghowen of 
Lake Erie, Ontario: Genesee Shale. 
Potyenatuus nasvrus, Hinde. (PI. XVI. fig. 22.) 
Base of tooth narrow, elongated, and straight, terminated at one 
end by a broad, flattened, depressed main tooth, which projects in a 
line with the base; below the main tooth, and making an acute 
angle with the base, is a small arm carrying three denticles ; on the 
base itself are twenty denticles of various lengths, Length of base 
13 line. 
Loc. North Evans, New York; Genesee Shale. 
