BUFFALO SOCIETY OF NATURAL SCIENCES 1 7 



guishable from Eurypterus maria. A bed, said to occur between a 

 horizon containing what is apparently a Clinton fauna (B 8x) and 

 one containing a Rochester (orLockport) fauna (B i9x)and numbered 

 B 16 h, contained the following remains: 



1. Small carapaces, belonging to species closely related to 

 or identical with Eurypterus maria, Hughmilleria shawan- 

 gunk and Pterygotus globiceps. 



2. A patch of integument with finely preserved sculpture 



identical with that ascribed to Stylonurus sp. 



3. Stylonurus myops. Fragmentary, medium sized carapace. 



4. Coxa, probably belonging to Hughmilleria. 



5. Small telson of an Erettopterus. 



Middle Siluric or Salinan. In the Middle Siluric of North America 

 are several interesting occurrences of eurypterids, and the first appear- 

 ance of well preserved individuals in large numbers. Specifically in- 

 determinable fragments of Hughmilleria and carapaces of Dolichop- 

 terus (cf. D. otisius) or Hughmilleria have been found along the 

 Pennsylvania-Maryland border in a hard black shale which is "sandy 

 at the top and pitted by rust-stained worm-tubes" (267, 5), and which 

 is interbedded between two sandstone members of the Keefer sand- 

 stone member of the McKenzie formation at the base of the Salina. 



Of far greater interest and importance, however, are the faunas 

 of the Pittsford and Shawangunk shales of New York and Penn- 

 sylvania. At Pittsford, Monroe County, New York, five species 

 (or varieties) of eurypterids have been found: Eurypterus pittsfordensis 

 Sarle, Hughmilleria socialis Sarle, H. socialis var. robusta Sarle, Ptery- 

 gotus monroensis Sarle and Stylonurus (Ctenopterus) multispinosus 

 Clarke and Ruedemann. This fauna is represented by numerous 

 individuals, many of them well preserved, and by many fragments, 

 but typical marine fossils are absent from the shales, although Crus- 

 tacea such as Emmelezoe decora and Pseudoniscus roosevelti occur. 

 The eurypterids are here preserved in a remarkable state of perfec- 

 tion, the fauna being found in two thin layers of the black shales 

 (lower one 1 foot 2 inches thick, upper one 10 inches thick) (240, 

 1082) and the eurypterids are in such abundance that some layers 

 are "literally packed" with the remains. The entire fauna from these 

 beds as reported by Sarle (240, 1081) is: Phyllocarida, 2; Synxi- 

 phosura, 1; Eurypterida, 6. 



In the associated dolomitic layers were found Graptolitida, 1; 

 Annelida (denticles), 3; Brachiopoda, 1; Pelecypoda, 1; Cephalopoda, 

 2; Ostracoda, 1. 



