LEZ NEW YORK STATE MUSEUM 
nite deposited on calcite crystals of the prevailing habit which latter were 
found to be deeply pitted with natural etchings. 
Type I [pl. 21, fig. 1]. Small crystals of this habit were noted on 
one specimen occurring in a thin layer partly covered by the larger individuals 
of type II to which they stand in close crystallographic relation. They 
evidently mark an earlier generation of calcite deposition than these latter. 
In habit they are quite steeply scalenohedral, the dominant forms being 
K: (2131) and 3: (6281). The polar edges of 3: are truncated in the positive 
sextants by narrow planes of the positive rhombohedron q. (7071). The 
combination is terminated by the negative rhombohedron 6. (0112). The 
positive rhombohedron p.(1011) is occasionally present as a series of 
minute planes. 
Type II [pl. 21, fig. 2-5]. Crystals of this type which are by far 
the most common to the occurrence are characterized by considerable 
complexity as well as by a strong twinning tendency which latter finds 
expression in nearly all of the crystals studied. 
The crystals are scalenohedral in habit with a somewhat rhombohedral 
aspect due to the dominance of the scalenohedron b: (7189) which lies very 
close to the fundamental rhombohedron. In the rhombohedral zone the 
rhombohedron p. (1011) is frequently present alternating with the low 
scalenohedron b: (7189) which latter, although clearly defined, is without 
question a built-up form more or less vicinal in character. The planes of p. 
are smooth but rather duil. The rhombohedrons m. (4041) and q. (7071) 
occur as narrow but extremely brilliant faces, giving excellent reflections and 
beveling the edges of U: (10.4.14.3) and 3: (6281) respectively. Small brill- 
iant planes of the prism b (1010) are present and the negative rhombohedron 
b, (0.14.14.1) was noted in relatively small development on several crystals. 
The rhombohedron 6. (0112) is universally present as brilliant faces 
which make excellent points of reference in this zone. 
The scalenohedron K: (2181) which is a dominant form of type I is 
present as a series of brilliant, well defined planes. The scalenohedrons 
U: (10.4.14.3) and $: (6281) are universally present. A new positive scale- 
