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NEW YORK STATE MUSEUM 



layers, the lower one i foot, the second I foot, 2 inches and the 

 upper 6 inches thick and is exposed for a short distance in the sides 

 of the ravine, where it contains the interesting fauna of the stratum 

 in excellent preservation. It is again seen on the highway on the 

 west branch of Onondaga creek near the west line of the quadrangle, 

 together with a small exposure of black shale. The lower black 

 shales are exposed just above the forks of the creek 1 mile south- 

 east from Indian Village, and the upper part of the formation in 

 the highway and cliff on the east side of Onondaga creek near the 

 south line of the Indian Reservation. 



This Agoniatites limestone can not be traced very far to the east 

 but westward it is continuous to Union Springs, Cayuga co. and 

 Phelps, Ontario co., where it loses its individuality. In the black 

 shales fossils are rare except at the base of the formation where 

 Liorhynchus 1 i m i t a r i s is very abundant and sometimes 

 produces calcareous lenses. With it are associated O r b i c u - 

 loidea minuta, Chonetes mucronatus, Actinop- 

 teria muricata, Pterochaenia fragilis, Stylio- 

 lina fissurella, O.rthoceras s 11 b 11 latum and a few 

 other species, all of which are of tenuous shell and rather diminutive 

 size, indicating the deterrent effect on growth of the conditions in 

 which the fauna was involved. Occasional remains representing the 

 arthrodirous fishes have been found. 



The Agoniatites limestone is more prolific in species which are in 

 large part peculiar to it and are often finely preserved, specially im- 

 portant and significant here being the assemblage of cephalopods. 

 The species which one may expect from this rock are as follows: 



Mesothyra? 



Proetus haldemanni Hall 

 Cyrtoceras alternatum Hall 

 C. liratum Conrad 

 Gomphoceras conradi Hall 

 G. fischeri Hall 

 G. ovi forme Hall 

 G. solidum Hall 

 Nephriticeras bucinum Hall 

 Nautilus liratus Hall 

 Discites marcellensis Vanuxcm 

 Parodiccras discoideum Conrad 



Agoniatites expansns Vanuxcm 

 Thoracoceras wilsoni Clarke 

 Orthoceras aptum Hall 

 0. marcellense Vanuxcm 

 O. constrictum Conrad 

 Enomphalus planodiscns Hall 

 Loxonema delphicola Hall 

 Macrochilina onondagensis Clarke 

 Lunulicardium enrtum Hall 

 Panenka vemtricosa Hall 

 Liorhynchus limitaris Hall 



