GEOLOGY AND PALEONTOLOGY OF THE SCHOHARIE VALLEY 301 



eru 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 S i e b e r e 1 1 a g a 1 e a t a . Layers 

 of chert are not infrequent and in some outcrops 

 form a constant and characteristic feature. The 

 lower layers are rich in Favosites hel- 

 d e r b e r g i a e 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: 



Fistiilipora torta Hall 

 Leptaena rhomboidalis (Wilckens) 

 Stropheodonta varistriata arata Hall 

 Spirifer perlamellosns 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 alt a alone 

 occurring at intervalsi. Several Stromatopora 

 beds occur in the upper part of the series, 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 : ' : 



Stromatopora (Syringostroma) sp. cc 



Spirifer vanuxemi Hall c 



S. corallinensis Grabau r 



S. eriensis Graltau var. c 



Camarotoechia hudsonica Grahau c ' 



Rhynchospira excavata Grabau rr 



Whitfieldella cf. nitida Hall rr I 



Gastropod ^' 



Leperditia alta c . •' ~ 



