LOWER SILURIC SHALES OF THE MOHAWK VALLEY 23 



The first 65 feet of the beds at Canajoharie (from the Glens 

 Falls limestone to the lower falls) consist of calcareous shale with 

 frequent small limestone seams near the base. The shale is deep 

 black, calcareous, hard and splintery, brownish weathering. It 

 contains : 



Diplograptus am.plexicaulis Hall (cc) 



Leptobolus insignis Hall (c) 



Schizocrania filosa Hall (c) 



Lingula curta Conrad (c) 



Calymmene senaria Conrad var. (c) 



Ctenodonta nuculiformis ? Hall (r) 



Primitiella unicornis Ulrich (r) 



An extremely rich zone was observed in the cliff directly above 

 the falls (65-120 feet from base). This has furnished: 



Diplograptus amplexicaulis (Hall) (cc) 



Corynoides calicularis Nicholson (c) 



Diplograptus (Mesograptus) putillus Hall (r) 



Lasiograptus eucharis (Hall) (c) 

 Sponge spicules 

 Spatiopora sp. ■ 



Leptobolus insignis Hall (c) 



Lingula curta Conrad (r) 



Dalmanella testudinaria (Dalman) (c) 



Rafinesquina alternata (Emmons) small (c) 



Plectambonites sericeus (Sowb.) H. & C. (c) 



Hyolithes pinniformis nov. (c) 



Prolobella ? trentonensis (Hall) (c) 



Pterinea insueta^ (Emmons) (r) 



Ctenodonta cf. nuculiformis (Hall) (c) 



Clidophorus sp. (c) 



Ctenodonta sp. nov. large (rr) 

 Whiteavesia sp. 



Clathrospira subconica (Hall) (c) 



Liospira cf. rotuloides (Hall) (c) 



Orthoceras sp. (r) 



Calymmene senaria (Conrad) (cc) 



Lepidocoleus jamesi (Hall & Whitfield) (c) 



Turrilepas filosus Ruedemann (r) 



Ulrichia ? bivertex Ulrich (c) 



Primitiella unicornis Ulrich (cc) 

 Minute Primitias 



^This last species, described by Hall in Paleontology New York, 

 1:291, is known only from this locality. Hall states of it: "This species 

 occurs in the lower black shale, or Utica slate, at Canajoharie, and is 

 known in the higher part of the group." 



