88 The American Geologist. Au^,^l.st, i89i 
latter layers bearing cjuite sparingly traces of conodonts, fishes and 
plants, with Lclorlnjnchus quadricostatus and Orhiculoidealodensis. 
Toward the top they again become argillaceous. 
The fauna of the upper and lower shales is very meager at the 
best, and consists essentially of these species : 
OonktUtcs unuttKjulnrls Conrad, Coleolus aclcuUnn Hall, 
Pleurotomaria nignlata Hall, Lunullcardium fragile Hall, 
Lclorhynchus iiiindrlcostatus Vanuxom, Orhleidoidca lodcnsis Vanuxem. 
This is a well known combination characterizing the black shales 
throughout their extent in this state, eastward and westward of 
this meridian. 
Shortly after the retreat of the Hamilton fauna and the first ap- 
pearance of bituminous sediments with this association of organic 
remains, there appeared an interesting incursion of species which 
invites special attention. This faunule has been studied only at a 
single outcrop in Bell's gully, on the east shore of Canandaigua 
lake, in a thin band of black shale but few feet from the base of 
the series and' distinguishable from that immediately above and 
below only in being slightly less sandy. It would be natural to 
expect, among the earlier portions of these sediments, some indi- 
cations of a more or less restricted return of the characteristic as- 
sociation of the Hamilton ; such indications, indeed, it is quite 
likely will be found, but this little assemblage is not of such a 
nature. The following species have been identified : 
Conodonts in considerable variety. 
Entomis sp. 
Fragments of an undetermined phyllocarid crustacean. 
OHhoccras sp. 
HyolUhes sp., unlike species of the Hamilton or succeeding faunas. 
Tentacidites sp. 
*StuHoUna fissnrella Hail ; not especially abundant. 
* Pleurotomaria capillarki Hall. 
*P. itxjfi Hall, var. tenuispira Hall. 
*P. niguUtta Hall. 
NucuUtes, sp. nov.; abundant. 
LtinuUcanUiuii, »i). nov.; a spinose species occuring botli in the Sty- 
liola layer and the Naples beds. 
CanUola Doris Hall, 
C. (Buchiola) retrostrlata von Buch, 
Phthonia like P. nodocostatci Hall, but persistently smaller in size. 
*Chonetes lepida Hall, 
Chonctes, cnf. nnrortt Hall, 
Twigs of PsiJoplii/ton or Rhnchioptcrlii. 
Tlie usual species of the black shales are thus seen to be almost 
wholly absent from this assemblage. Such of the species (those 
