G, magna, G. alveata, Actinopteria Boydii, Pterinea flabel- 
lum, Nucula Randalli, N. trata, N. bellistriatus, Gonto- 
phora Hamuiltonensts, G. truncata, Pterinopecten conspectus, 
P. regularis,. 
There are also several species of pteropods found, they 
belong to the genera Coleolus, Hyolithes and Conularia. 
Cephalopods continue to be found, although not as pro- 
fusely as at the beginning of this period. The more com- 
mon orthocerata are: O. sublatuim, O. crotalum, O. exile; 
those more rarely found are: O. sprssum, O. constrictuma, 
O. agea. 
The Nautilus maxinus is another large cephalopod 
that is often found, neither are the Gonzatites discoideus, 
or the G. uniangularis very rare. 
Crustacea.—omalonotus Dekayi is a large trilobite 
abundant in some of the harder layers. On account of the 
favorable character of these rocks for specimens of all 
kinds, it is not difficult to obtain entire specimens. 
Phacops rana, which we found sparingly in the Upper 
Helderberg Period, is now found very abundantly. 
Dalmanites calliteles is another trilobite that is quite 
abundant in the shale of this group. 
Echinocaris punctata is a phyllopod that is often found 
in the blacker shales. 
Fishes.—Occasionally a fish spine is the only trace of 
vertebrates that have as yet been found. 
Plants.—Lepidodendrons, which in the Carboniferous 
became so plentiful, ferns, fucoides and other marine 
plants are all found in this group. 
Tully Limestone.—Immediately overlying the Hamil- 
ton Beds we find an interesting limestone formation, hav- 
ing numerous exposures in our county. Itis the Tully 
Limestone, and is interesting because it is the highest 
mass of limestone (geologically) in the State. It has not 
an extensive geological distribution, being found in only 
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