18 THE GENESEE CONODONTS 
PRIONIODUS MURICATUS, Spec. Nov. 
Plate V, fig. 7. 
Base long and arched, with a pronounced central cavity beneath. 
From six to nine tenuous pointed denticles are closely arranged 
on either side of the slender, acute central cusp, which is ovoid 
in cross section. From the Conodont bed at Eighteen Mile Creek, 
where perfect specimens are very rare ;—the slender and brittle 
tips of the teeth being nearly always more or less broken. The 
example figured shows better than any other, the basal cavity 
beneath the main.cusp which is characteristic of all Conodonts. 
From the Conodont bed of Eighteen Mile Creek. 
PRIONIODUS BRAW WS. SerceeNov 
Plate VIII, fig. 5. 
Base long, narrow and strongly arched. Above the arch is a 
short, compressed, expanded tooth, somewhat bent and very 
blunt, being wider at the summit than at the base. On one side 
of this main cusp is a row of thirteen robust denticles, uneven 
in height, and closely opposed, and on the other side are about 
eight smaller and likewise uneven denticles. Rare in the Cono- 
dont bed of Eighteen Mile Creek. 
PRIONIODWUS SPATULA WS wSPeei Nowe 
Plate VIII, fig. 9. 
Base short and arched. Main cusp enormously expanded and 
compressed, wider about halfway of its height than either above 
or below, its outer face strengthened by a midrib or keel, and its 
apex rounded. On either side, a row of three or four stout, 
sub-cylindrical, blunt denticles. Rare in the Conodont bed of 
Eighteen Mile Creek. 
PRIONIODUS MACRODENTUS, Spec. Nov. 
Pilates Vil hea l0: 
Base arched and wide, the margins curled up lke the brim of 
a hat. Near one end a large, robust, spike-shaped fang projects 
obliquely upward and outward. This main cusp is bordered on 
one side by a row of about eight large, conical, pointed teeth of 
varying heights, rather closely arranged, their bases fused to- 
gether. On the other side there are but one or two smaller 
denticles. From the Conodont bed of Eighteen Mile Creek. 
PRIONIODUS ARMAMOS = EUEND I= 
1879. Prioniodus armatus, G. J. Hinde, Quart. Journ. Geol. Soc.. 
Viol SOOO Sp. 3600) Plate Davee nics» 20p anda Ze 
