Page:Quarterly Journal of the Geological Society of London, vol. 35.djvu/431

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and Devonian Conodonts.
361

of Genesee Shale. Also from North Evans, New York, in Genesee Shale. Pkioniodt/s spicatus, Hindc. (PI. XVI. figs. 1, 2, 3.) Basal portion straight, narrow, and convex; at one extremity a straight or slightly curved main tooth which is produced below the horizontal base to a pointed projection. A variable number of straight slender denticles aro present on the base, and between these are intercalated still smaller denticles. Length of base | line, of main tooth | line to g line. Loc. Bear Creek, Ontario ; North Evans, New York : Genesee Shale. Prioniodus Pandeiii, Hindc. (PI. XYI. fig. 4.) A relatively very large, slightly curved, depressed convex main tooth springs from one extremity of the narrow horizontal base ; at- tached to the base of the main tooth, and extending downwards, is a prominent spike-like projection, which has on its upper surface the bases of what appear to have been four stout denticles ; on the hori- zontal base are the lower portions of six denticles. Length of the large tooth lg line, of the projection | line, and of the base g line. This species is allied to P. tulensis, Pander (Monograph, p. 30, tab. 2 a. fig. 19) which has also a somewhat similar produced spike below the main tooth, with a single denticle on it. P. tulensis is from the Carboniferous Limestone in the province of Tula, llussia. I have named this species in memory of Dr. Pander, the first dis- coverer of Conodonts. Loc. Kettle Point, Ontario : Genesee Shale. Also from North Evans, New York : in the " Conodont-bed " of the Hamilton group. Pkioniodus ? ALATtrs, Hinde. (PI. XYI. fig. 5.) A comparatively large, triangular, depressed convex main tooth with a narrow arched base, one arm of which is produced obliquely downwards and carries five, short, blunted denticulations on the ex- terior edge. This tooth varies greatly from the more typical forms of Prioniodus, in its triangular form and in having the basal portion but very indistinctly marked off from the tooth itself; the smaller denticulations have also the appearance of being only prolongations of the thin border of the main tooth. Length 1| line, greatest width | line. Loc. North Evans, New York: in the "Conodont-bed" of the Hamilton group. Genus Polygnathus, Hinde, nov. gen. I propose this genus for an animal possessing numerous minute and variously formed Conodont teeth and similarly minute tuber- culatcd plates grouped together, but of which the natural arrange- ment is not at present known. This meagre definition is all that is afforded by the single example of the genus met with, in which about twenty-four entire and frag-