GEOLOGY AND PALEONTOLOGY OF THE SCHOHARIE VALLEY 301 



era part of the mountain. Numerous boulders 

 are scattered or piled up in fences on the moun- 

 tain and from these the fossils may be obtained. 



Feet 



Coeymans limestone 42-45 



This is a compact, finely crystalline, generally 

 dark colored lime sandrock with many fossils, 

 chief among which are Atrypa reticu- 

 laris and Sieberella galeata. Layers 

 of chert are not infrequent and in some outcrops 

 form a constant and characteristic feature. The 

 lower layers are rich in Favosites hel- 

 derbergiae and are well exposed in the city 

 quarry. The formation generally makes a cliff 

 which is one of the characteristic features of 

 the mountain. Above the cliff is a sloping bank 

 formed by the thinner bedded upper Coeymans 

 strata, which are transitional to the New Scot- 

 land. The common species here are: 



Fistulipora torta Hall 



Leptaena rhoniboidalis (Wilckens) 



Stropheodonta varistriata arata Hall 



Spirifer perlarnellosus Hall 



Atrypa reticularis Linne 



Sieberella galeata {Conrad) 



With these are other species more characteristic 

 of the higher beds. 

 Manlius limestone 55 



This rests unconformably on the upturned Hud- 

 son river slates, the contact being exposed at the 

 northern end of the mountain near the old 

 Greenport tavern, at the place where the great 

 spring of the Hudson aqueduct issues. The rock 

 is throughout a banded lime mudrock and fossils 

 are extremely rare, Leperditia a 1 1 a alone 

 occurring at intervals. Several Stroma topora 

 beds occur in the upper part of the scries, the 

 highest of them forming the terminal member 

 of the Manlius. In it occurs a modified Cobles- 

 kill fauna, the following species having been 

 found : 



Stroniatopora (Syringostroma) sp. cc 

 Spirifer vanuxemi Hall c 

 S. corallinensis Grdbau r 



S. eriensis Grdbau var. c 



Camarotoechia hudsonica Grabaa c 

 Rhynchospira excavata Oraban rr 

 Wliitfieldella cf. nitida If all rr 

 Gastropod 

 Leperditia alta c 



