420 ‘ NEW YORK STATE MUSEUM 
pearly calc spar, very large masses of coarse agate, quartz passing 
into chalcedony, petrosilex and quartz crystals” (p. 73). 
Substantially the same description of the Calciferous sandrock is 
given in Prof. Eaton’s Geological nomenclature (p. 12-13). 
In the First report on the geological survey of the third district Mr 
Conrad says ‘“‘ The general inclination [of the Calciferous sandrock] 
is 4° or 5° to s. w. which causes the rock to be generally lost to 
observation to the south of the Mohawk except upon the immediate 
bank of the river and that of the canal whilst it rises with the hills 
on the opposite shore, frequently however concealed by limestone.’ 
In the Second report of the third district, Vanuxem restates the 
features of the Calciferous sandrock, remarking that “this rock is 
very variable in character and composition, . . . and appears to 
contain more carbonate of lime in its composition at Tribeshill 
and in the small streams between Amsterdam and Crane’s village 
than on the western side of Montgomery county.2” A few fossils 
are mentioned as occurring in the upper layers of the rock (p. 283). 
In Vanuxem’s final Report on the third district, the Calciferous 
sandrock is said to embrace three masses. The first is siliceous, 
compact, the second is a “ mixture of fine yellow siliceous sand and 
carbonate of lime” and is the mass from which the name of the 
stage was derived, the third mass is a “mixture of Calciferous ma- 
terial which is usually yellowish, very granular and sparkling when 
fresh broken and a compact limestone which resembles the Birdseye 
limestone.’’® These constitute the Fucoidal layers. The latter 
rock is more fully described as follows: “These layers are . . . 
readily distinguished from the calciferous rock by their disposition in 
thick strata, many parts of which when long exposed show a struc- 
ture as if formed of numerous thin ones. The mineral composition 
is more varied, showing frequently a mixture of Calciferous sand- 
rock and Birdseye limestone . . . It often presents ramose 
forms usually composed of the Calciferous portion (p. 35).. The 
peculiar mode of weathering of this rock is also mentioned by 
Emmons. 
In the 13th annual report of the state geologist (1893) five pages are 
devoted to the consideration of the Calciferous formation in the 
*Loc, cit, Assembly doc. no. 161, p. 160. 
"Loc. cit. Assembly doc. no. 200, p. 259. 
*Geology of New York, pt 8, p.30. 
‘Geology of New York, pt 2, p, 105; see also Ayriculture of New York, 1846, 1:119.. 
