A RECURRENT PITTSFORD (SALINA) FAUNA 



BY EUDOLF RUEDEMANN 



The discovery of a faunule consisting of eurypterids, crustaceans 

 and a few brachiopods and mollusks in black shale intercalated near 

 the base of the Salina beds led to the differentiation of these basal 

 beds by Doctor Clarke (1903) as Pittsford shale. 



At the same time the overlying " Salina shales " of earlier authors 

 were separated into the Vernon and Camillus shales. These red, 

 green and gray shales with intercalated abundant gypsum beds and 

 flaggy dolomites, though reaching a combined thickness of a thousand 

 feet, have proved nearly barren of fossils until two years ago when 

 Mr Shelley Crump of Pittsford obs-erved fossils in the Vernon shale 

 brought out of the barge canal at Pittsford, N. Y. He informed 

 Prof. G. H. Chadwick in Rochester of his discovery, who in turn 

 imparted the interesting information to the State Museum. 



Two weeks collecting by C. A. Hartnagel and an equal time given 

 the work by the writer and his assistants have altogether furnished 

 but twenty-six drawers of material, which proves that fossils are very 

 rare even under the extremely favorable condition of collecting from 

 an enormous dinnp pile. The novelty and peculiarity of the faunule, 

 however, fully repaid for the often discouragingly slow work of collect- 

 ing. 



The writer made a special effort to get noneurypterid material 

 that would aid in clearing up the question of the habitat of the 

 eurypterids which form the dominant element of the fauna and 

 succeeded in finding a small number of brachiopods and mollusks. 



As in the Pittsford shale, most of the fossils were obtained in the 

 dark gray to black shale bands and the dolomite slabs. There occur, 

 however, fossils also in the green shale, especially ostracods, and very 

 rarely eurypterids; and Professor Chadwick informs me that he has 

 also found ostracods in the red shale. 



The following is a list of the forms found : 

 Lingula semina Ruedemann c 

 Lingula sp. • rr 

 *Rhipidomella sp. rr 

 *Atrypa reticularis (L) rr 

 *Trochoceras aff . costatum Hall rr 



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