GEOLOGY OF THE ATTICA AXD DEPEW QUADRANGLES 1 7 



pteropods, 29 lamellibranchs, 50 brachiopods, i crinoid, 8 bryozoans 

 and 7 anthozoans. The common forms are : 



Phacops rana Green 

 Cryphaeus boothi Green 

 Proetus rowi Green 

 Platyceras auriculatum Hall 

 P. thetis Hall 

 Nautilus magister Hall 

 Orthoceras nuntium Hall 

 Styliolina fissurella Hall 

 Diaphorostoma lineatum Hall 

 Pterinea flabellum Conrad 

 Actinopteria decussata Hall 

 Modiomorpha subalata Conrad 

 Palaeoneilo tenuistriata Hall 

 Stropheodonta demissa (Conrad) 

 Leptostrophia perplana (Conrad) 

 Rhipdomella vanuxemi Hall 

 Orthothetes arctostriatus Hall 

 Chonetes lepidus Hall 

 C. scitulus Hall 



Spirifer mucronatus (Conrad) 

 Sp. granulosus (Conrad) 

 Sp. fimbriatus Hall 

 Sp. subumbona Hall 

 Ambocoelia umbonata (Conrad) 

 Athyris spiriferoides (Eaton) 

 Atrypa spinosa Hall 

 Camarotoechia dotis Hall 

 Tropidoleptus carinatus (Conrad) 

 Liorhynchus multicostum Hall 

 Pleurodictyum stylopora (Eaton) 

 Streptelasma rectum Hall 



Exposures. There are many fine exposures of the Ludlowville 

 shales on these quadrangles. The upper beds outcrop along Bowen 

 brook and the entire section or nearly all of it along ^lurder creek 

 north of Darien ; along Ellicott creek one and three- fourths miles 

 west of Darien Center, and along Spring creek and the Erie Rail- 

 road east of Alden. The middle l)eds are displayed in the bed of 

 Cayuga creek a mile south and southeast from Marilla Station. 

 At the fall in Buffalo creek at the Bullis bridge, 2 miles west of 

 Marilla, the exposure of the upper beds and the contact with the 

 Tichenor limestone is exceptionally large and favorable for the 

 collection of fossils^ and the middle and lower shales are displayed 

 along the bed and banks of the stream to Elma and Blossom. The 



