CALCITES OF NEW YORK 123 
habit. The rhombohedral zone in this instance is composed of the nega- 
tive rhombohedrons 6. (0112), 9. (0221), ®.(0.14.141) and T. (0.28.28.1) 
developed to about equal habit. The positive scalenohedron K: (2131) 
is present, developed to a considerable habit; the planes of this scaleno- 
hedron are striated parallel to the zone [1011.1120]. The negative scaleno- 
hedron Y noted in the preceding combination is here present in small 
development, the planes in both instances giving good reflections. The 
dihexagonal prism ¢ (3140) is also present in planes of relative small develop- 
ment which yield fair reflections. 
type Vie |ple27, ue. 2) A combination of this type, represented 
by small, yellowish, rhombohedral crystals, is shown, in figure 1. These 
crystals, which were in few instances observed to be doubly terminated, 
have for the dominant form the negative rhombohedron F. (0.12.12.5) 
present as a series of roughened and somewhat rounded planes. The 
prism b(1010), also represented by rounded planes marked by vicinal 
prominences, merges into F. with no sharply marked edge. Small bright 
planes of the rhombohedron p. (1011) modify the polar edges of F. The 
combination which is shown in figure 2 and which is evidently of a built-up 
character was observed on several specimens in individuals averaging 
5 millimeters in length. These are rhombohedral in habit the compound 
individual consisting of a steep rhombohedral element combining the nega- 
tive rhombohedrons ¢. (0221), F. (0.12.12.5) and o.(0.11.11.4) developed 
to about equal habit; this middle section is terminated by a superposed 
element in parallel position combining the negative rhombohedrons 
6. (0112) and W. (0.17.17.1). Reentering angles mark the juncture of the 
superposed elements as shown in figure 2a which represents a section 
normal to the rhombohedral zone. 
Type VII [pl. 27, fig. 3, 4]. Crystals of this type are notably larger 
than those heretofore described and are characterized by rather dull faces. 
The combination shown in figure 3 consists of the positive scalenohedrons 
H: (3142) and »(10.3.13.2) terminated with the rhombohedron (0112). 
Of these the scalenohedron H: (3142) is represented by dull and roughened 
