24 THE GENESEE CONODONTS 
different aspects when imbedded in the shales. I have figured 
on Plate X, figs. 1-9, examples of this species in various aspects. 
Figs. 6 and 8 are views of the underside, showing the diamond- 
shaped cavity common to all Conodonts from this region. It will 
be noted that rights and lefts can easily be distinguished. 
PRODYVGINAMRE OS GRISsVAGeClSe iran ies 
1879. Polygnathus cristatus, G. J. Hinde, Quart. Jour. Geol. Soc., 
Voll XOXO) sp: 366) Plate Dav aie thio iil: 
1879. Polygnathus dubius, G. J. Hinde, Quart. Journ. Geol. Soc., 
p. 363 (crested teeth), Plate XVI, figs. 16, 18. 
1886. Polygnathus cristatus, J. M. Clarke, Report of the State 
Geologist of New York, Plate A-1, fig. 20. 
1886. Polygnathus dubius, J. M. Clarke, Report of the State Geologist 
of New York, Plate A-1, fig. 1. 
This, like the preceding species, was described under two names 
by Dr. Hinde, but there can be no question that his drawings 
as well as those of Dr. Clarke are of different aspects of the 
same form. Both Hinde and Clarke have figured upper and 
profile views. The upper surface of the plate is ornamented on 
each side of the central ridge with a double row of tubercules 
which have a tendency to a linear arrangement. The species 
occurs in the Portage group, and Hinde described it from the 
Conodont bed, but if it actually came from there, it must be so 
rare that it has not appeared in later collections. I suspect that 
it came from a Portage shale locality. 
ROLEYGNADHUS ORDINATUSS SPEec Nov: 
Plate X, figs. 10, 11. 
Plate lanceolate in outline, the upper surface convex in its 
longest axis, and deeply grooved longitudinally. A crenulated 
central crest arises from this groove, and is produced beyond one 
end of the plate. The main plate is ornamented with tubercules, 
often grouped in one or two longitudinal rows on either side of 
the crest. 
Conodont bed of Eighteen Mile Creek. 
POLYGNATHUS ROMA S SPEC = Nov 
Plate X, figs. 13-16. 
Dental plate narrowly lanceolate, its margins curled upward 
like a slightly withered leaf. In profile the plate is sigmoidal 
in outline, while viewed from above there is a longitudinal medial 
furrow, from which arises a slender, crenulated keel. This keel 
extends beyond the main plate as an expanded process, armed 
above with a few serrations. The upper surface of the main 
plate is covered with minute tubercules. 
Conodont bed of Eighteen Mile Creek. 
