ROCHESTER AND ONTARIO BEACH QUADRANGLES 27 



P. sulcata Hall Hormotoma whiteavesi Clarke of Ruede- 



P. crenulata Whiteaves mann 



Eotomaria durhamensis Whiteaves Coelidium macrospira Hall 



E. areyi Clarke dr" Ruedemann C. cf. vitellia Billings 



E. kayseri Clarke dfRuedetnamt Macrochilina sp. 



Lophospira bispiralis Hall 'Eviom^'h.QlviS>ia.\r:c\\\\d.\' Clarke df Rue de-- 



mann 



Cephalopods 



Orthoceras trusitum Clarke cSr' Ruede- Cyrtoceras cf. brevicorne Hall 

 mann C. bovinum Clarke &f Ruedemann 



* Dawsonoceras annulatum z/ar. ameri- Trochoceras desplainense McChesney 

 canum. Foord {w2iV.) Poterioceras sauridens Clarke df Ruede- 



*Kionoceras darwini Billings mann 



K. cf. medullare Hall Phragmoceras parvum Hall 6^ Whit- 



Cyrtoceras arcticameratum Hall field * 



C. erodes Billings 



*Cornulites arcuatus Conrad 



Vermes 



Crustacea 



Leperditia balthica var. guelphica *Calymmene niagarensis HaU 



Jones Proetus sp. 



L. sp. 



Salina formation. This term was introduced by Dana and is 

 used in place of the older name " Onondaga salt group." In central 

 and western New York, the Salina outcrops in a broad belt 5 to 20 

 miles wide. The formation thins out entirely in Albany county, 

 where the upper part overlaps the Champlainic or Lower Siluric 

 strata. To the west it has been traced as far as Georgian bay in 

 Canada. The maximum thickness of the formation is 1200 feet 

 in Wayne and Cayuga counties and thins both to the east and to 

 the west of this section. 



In the vicinity of Rochester, the entire thickness is about 600 feet 

 and at Buffalo, 450 feet. From the' soft nature of the rocks of this 

 formation, no conspicuous ledges are anywhere to be seen and in a 

 large degree the formation has been so covered by glacial drift that 

 outcrops are rare. In western New York, the rocks all have a south- 

 erly dip, and as the soft Salina shales occupy a position between the 

 hard rocks of the Lockport and Onondaga formations, the drainage 

 is often seriously affected, specially where there is but a small amount 

 of glacial drift. Eastward from the Rochester region, the Salina 

 strata are covered by a large number of drumlins and the swamps 



