458 ; NEW YORK STATE MUSEUM 
weathers ash-white with a delicate bluish tint. The peculiar plant-, 
like reticulation of Phytopsis tubulosa Hall is very 
conspicuous in the rock at this locality since the former weathers 
buff whereas the matrix weathers nearly- white. The vertical 
columns are larger than in the rock of this horizon near Newport 
and Littlefalls where they are quite small and composed of calcite, 
while in the Birdseye of the lower Mohawk they are composed of 
argillaceous or pyritiferous material. ,Within the limits of the ex- 
posure, a small quarry, the limestone varies from 2 to 4 feet 
in thickness, both delimiting terranes being in place. The upper 
surface of the subjacent Calciferous is uneven and hence the line 
between it and the overlying Birdseye is very sharply drawn. 
Above, the Birdseye seems to pass into the superjacent Black river 
without any sharp line of demarcation. 
The following species were obtained from the Black river lime- 
stone, C>: 
I Monticulipora (Prasopora) lycoperdon Say (aa) 
Branched form 
2 Streptelasma corniculum Hall (c) 
3 Streptelasma profundum Hall? (r) 
4 Stictopora elegantula Hall | (r) 
5 Stictopora cf. ramosa Hall (r) 
6 Phytopsis tubulosum Hall? (r) 
7 Columnaria alveolata Goldfuss (c) 
8 Zygospira recurvirostra Hall (c) 
9g Plectambonites sericea (Sowerby) Hall and Clarke (r) 
10 Rafinesquina alternata (Con.) Hall and Clarke (c) 
11 Asaphus platycephalus Stokes (r) 
12 Hormoceras tenuifilum Hall (r) 
13 Crinoid segments 
The base of the Trenton stage in this section is 380 feet A. T. 
and in the Quarry hill one and one half miles to the north the base 
of the Trenton stage is 600 feet A. T. This gives a south dip of 
1.47 feet a mile. By barometer the former point is 175 feet above 
the level of the Mohawk and the latter 400 feet, which gives the dip 
as 150 feet a mile to the south-southwest. 
Along the creek which empties into the canal one and three- 
tenths miles due west of Crane’s village station the following sec- 
tion was measured (46E): 
