34 NEW YORK STATE MUSEUM 



miles south of the mouth of the Snook kill, limestone bands one to 

 two inches thick appear, which are entirely composed of brachiopod, 

 trilobite and crinoid fragments, but collecting will not furnish any- 

 thing but the common brachiopods Dalmanella testudi- 

 naria, R a f i n e s qu i n a , P 1 e c t a m b o n i t e s seri- 

 c e u s and the trilobite Trinucleus concentricus. 

 The surrounding shales contain : Corynoides calicu- 

 laris, Cl im ac ogr ap t u s spini.ferus, C. putil- 

 lus, Lasiograptus eucharis. The last mentioned form 

 was also observed to fill a band of black shale about three miles up 

 the Snook kill, where it is associated with Trocholites 

 a m m o n i u s . 



The following inferences in regard to this belt of black shales in 

 Saratoga county seem of importance for the present inquiry : 



1 These shales which have hitherto been considered as good 

 typical Utica shales, are in their lithologic aspect like the latter but 

 lack the strong calcareous admixture and for that reason rarely effer- 

 vesce with acid. But, as we shall show later, they are lithologically 

 quite distinct from the belt of Snake Hill beds, which adjoin them to 

 the east, the latter containing not only numerous intercalations of 

 grit and sandstone beds, as at Snake hill, but being also thinner 

 bedded, more fissile, more argillaceous and less carbonaceous, 

 approaching in their character the Frankfort shale. 



2 The fauna of these shales is that of the Canajoharie beds of 

 the Mohawk valley, as shown by the occurrence of and dominance of 

 Corynoides calicularis, Diplograptus am- 

 plexicaulis, Glossograptus quadrimucrona- 

 t u s mut. cornutus, Lasiograptus eucharis. 



3 These shales rest also in this belt on the basal Trenton (Glens 

 Falls) limestone. This relation was observed, as above stated, at 

 Hudson Falls. It may also be inferred from the outcrops on the 

 Glowegee west of Saratoga, which lie but a short distance south 

 and in the dip of the belt of basal Trenton (Glens Falls) limestone 

 passing west of Saratoga through Rowland's mill and Rock City 

 Falls. 



FRANKFORT SHALE 



The type locality of the Frankfort beds is the gorge of Moyer 

 creek at Frankfort, about nine miles southeast of Utica. A parallel 

 series of fine outcrops is furnished by Steels creek, only two miles 

 away, in the so-called Ilion gulf. 



