CALCITES OF NEW YORK 2a 
Type I [pl. 25, fig. 1]. Crystals of this type are simple combina- 
tions of the negative rhombohedron 8. (0112) and the prism b (1010), the 
latter form being developed through a wide range of habit from a series of 
narrow triangular faces to a dominance which produces crystal individuals 
having a relative length of two or three times their diameter. The pris- 
matic faces are invariably striated vertically. 
Type II [pl. 25, fig. 2-6]. Crystals of this type are characterized 
by the presence of the steep positive scalenohedron © (15.4.19.3). In the 
combination shown in figure 2 the dominance of this scalenohedron produces 
long slender crystals, terminated by the negative rhombohedron 6. (0112). 
Crystals of this combination, which are of frequent occurrence, reach a 
maximum length of 25 millimeters. Inclusions of pyrite were noted in 
several instances, outlining the faces of a steep positive scalenohedron, 
possibly ). A more rhombohedral variation of this type is shown in figure 
3 and was noted on a number of specimens. In this instance the prism 
a (1120) is present truncating the middle edges of the scalenohedron. The 
basal plane o (0001) and the positive rhombohedron m. (4041) are occa- 
sionally present in crystals of this habit. The combination shown in figure 
4 is of more uncommon occurrence in crystals of this type than either of 
the two preceding habits. The crystals are characterized by the equal 
development of the rhombohedrons 3. (0112) and A. (0772), the scaleno- 
hedron D being reduced to comparatively small development. The prism 
a is sometimes present in this combination. Twinning parallel to the basal 
plane o and the negative rhombohedron 3. is frequent with crystals of this 
type the resulting combinations being shown in figures 5 and 6. 
dy perllien| plea 2ontiow ll —olannCuysrals of type Wil are- prismatic i 
habit and are chiefly characterized by the dominance of the prism a (1120) 
and the negative rhombohedron 3.(0112). The combination shown in 
figure 1 which was noted on several specimens, presents in addition to the 
two forms characteristic of the type the positive scalenohedron © (15.4.19.3) 
of type II and the negative scalenohedron ¢(3.15.18.2). The latter form 
which was previously noted under Union Springs is present as a series of 
