156 



PLATES. 



Poly(;nathus PENXATUS. Hinde. (Fi<;-. 39.) ((iu;iit. Jour. 

 Geol. Soc, Vol. XXXV., p. 366, PI. XVII. ) 



Distinguishing Characters. — P^loiiuate. ovnl out- 

 line; (le|)ressed long'itudiiial furrow ; slender cen- 

 tral keel, produced beyond main portion, and 

 bearing tubercles; lateral ridges. 



Found in the Conodont bed of the (ienesee, at 

 Section 1 (abundant). (Hinde.) 



PoLYuxATiirs Tri$i:i{( ri.ATis. Hinde. 

 (Fig. 40.) (Quart. Join-. Geol. Soc, 

 Voh XXXV., p. 366, PI. XVH. ) 



Distinguishing Characters. — L( )bate 

 foi-ni : ])roduced and tuberculated cen- 

 ti'al keel ; converging rows of tubercles ; 

 reverse side smooth. 



Found in the (,'onodont bed of the 

 Genesee, at Section 1. ( Hinde. ) 



Polygnathus CRiSTATUs. Hinde. (Fig. 41.) 

 (Quart. Jour. Geol. Soc. Vol. XXXV.. p. 366, 

 PI. XVH.) 



Distinguisliing Characters. — ()\'al outline, 

 depressed convex expression: prominent cren- 

 ulated keel; tAvo I'ows of tul)ercles on either 



Fig. 41. Puhjgna- side of kccl. 

 thus cristatiis, x 13 n • i < 



(after Hinde). Fouud ui the ( ouodout bed oi the Genesee, 



at Secti<m 1 . ( Hinde. ) 



Poly a x a thus triw atus. Hinde. 

 (Fig. 42.) (Quart. Jour. (leol. Soc, 

 Vol. XXXV.. ]). 366, PI. XVIL) 



Distinguishing Cliaracters. — Sub-tri- 

 angular outline of plate; median keel, 

 not extended ; convex, tuljerculated sur- 

 face. 



Found in the Conodont bed of the 

 Genesee, at Section 1. (Hinde. ) 



Fig. 40. F'i)Ii/gnaflttiti tuber 

 culutus, X 13 (after Hinde). 



Fig. 43. Poh/f/nathiis 

 truncatus and P. tniiira- 

 tus, var. X 13 (after Hinde). 



