CALCITES OF NEW YORK 73 
crystals average 5 millimeters in vertical length and are clustered in thick 
aggregates; in no instance was a doubly terminated individual noted. In 
habit the crystals are rhombohedral, the dominant form being the negative 
rhombohedron ¢. (0221) modified by a well developed series of forms lying 
in zone [0112.1011.1120]. Inthe combination shown in figure 5 the positive 
rhombohedron p. (1011) which truncates the polar edges of 9.is developed 
as a series of narrow planes of great briluancy. The combination is ter- 
minated by the positive scalenohedron e: (4156), the second order pyramid 
=(1123) and the negative rhombohedron 3.(0112). The planes of e: are 
narrow and somewhat striated parallel to the zone; those of = are brilliant 
and yielded fine reflections. The positive scalenohedron K: (2131) is present 
as a series of bright, striated planes of fair development. Small, bright 
planes of the positive rhombohedron m. (4041) were noted on one crystal 
of this habit. A variation of this type is shown in figure 6 which differs from 
the combination above described in the greater development of the modi- 
fying zone and in the absence of the negative rhombohedron ¢.. The 
crystals of both habits occur intimately associated on the same specimen. 
SUMMARY OF MEASURED AND CALCULATED ANGLES 
LETTER ANGLE | Nee MEASURED | CALCULATED 
| READINGS | 
| ° / ° / 
7 2% IIB 3 PATS) 10 28 494 28 39 
18 8.98 UNDER e THOR 2 59 403 59 20 
3. 25. Diy & OL We Tee 10 68 «6 68 124 
Oa AVA 0112 : 0991 6 70 11 70 103 
jDs 3 ial, 1011 : 4041 1 31 2, 31 104 
io, 2 ink, 4041 : 4401 1 114 4 iia 1@ 
p. 39. 1011 : 2021 1 107 46 107 433 
9. 29. 220i O22 Ht 101 5 101 9 
p. ie: 1011 : 4156 5 LOM B3% Ole 24 
Crazies 4156 : 5146 3 13 6 13 4 
Dk: 1011 : 2131 3 29 20 29 ey, 
KeEaKke PUB 2 BAIL 1 35 46 35 36 
p: =N: 1011 : 5382 2 34 33 34 28 
gi 1 g: Giallo. 2a OSes, 3 Somes 53 584 
202 es Gaielonle: (eOrlse> 3 21 4 21 1 
