572 Wm, F. Prouty — Meso-Silurian Deposits of Maryland. 



* Rhipidomella subcirculus (Simpson) 

 Rhipidomella hybrida (Sowerby) 



f Phynchonella (tennesseensis) ? Roemer 



Schuchertella supblana (Conrad) 



Schuchertella tenuis Hall 



Spirifer crisp us (Hi singer) 



Stropheodonta corrugata (Conrad) 



Stropheodonta corrugata var. pleuristriata (Foerste) 



Stropheodonta sp. nov. 



Stropheodonta sp. nov. 



Ctenodonta sp. nov. 



Pterinea emacerata (Conrad) 



Bucanella trilobata (Conrad) 



Conularia sp. 



* Diaphorostoma niagarensis Hall 

 Platyceras sp. nov. 



Platyceras niagarense Hall 



Trochoceras sp. 



f Dalmanites limulurus (Green) 



* Homalonotus delphinocephalus (Green) 

 Cornulites sp. nov. 



Immediately overlying the Dalmanites limulurus zone there 

 is a fossiliferons horizon of some 3 to 15 feet in width, which 

 contains great numbers of Nucleospira pisiformis and some- 

 times a few Schuchertella sp. nov. This Nucleospira pisi- 

 formis zone, which occurs in the calcareous shale and limestone 

 layers, is overlain by some 150 feet of limestone and shales in 

 which the fossils are fewer and more scattered. 



This latter division has given us the following species : 

 Puthotrephis gracilis var. intermedia Hall 



* Favosites niagarensis Hall 

 Camarotoechia neglecta Hall 



* Homeospira evax var. nov. 

 Lingula sp. nov. 



Orbiculoidea sp. nov. 



Clidophorus sp. nov. 

 Ilormatoma. sp. nov. 



f Ilormatoma sp. nov. 



Near the top of the formation and usually between 50 and 

 80 feet below the ''disintegrated yellow rock" of the Salina 

 (the Niagara-Salina line) there occurs a band some 30 feet in 

 thickness which is here called the Camarotoechia sp. nov. zone* 

 It has yielded the following species : 



f Camarotoechia sp. nov. 



f Camarotoechia obtusiplicata Hall 



Camarotoechia neglecta Hall 



Lingula lamellata Hall 



Spirifer sp. nov. 



Clidophorus sp. nov. 



Cuneamra sp. nov. 

 * Abundant. f Very abundant. 



