Whitlock — Calcitefrom West Patterson, W. J. 427 



mal to the bounding surface. They are semi-transparent and 

 contain numerous inclusions of specular hematite in minute 

 aggregates. Hematite in microscopic, reddish, metallic plates 

 in some instances fills the interstices between the crystals. The 

 crystals of type II are rhomboheclral-scalenohedral in habit. 

 A well developed series of negative rhombohedrons character- 

 izes this type, the planes in the rhombohedral zone being sharp 

 and brilliant. 



The two positive scalenohedrons noted, M (8*4 - 12-5) and H : 

 (3695) in the zone [0001*2131], consist of smooth and some- 



what dull planes but yielded fair reflections. The latter of 

 these is _new. Two negative _scalenohedrons in the zone 

 [0221-1220], p i (1311) and q \ (2461), give sharp, brilliant reflec- 

 tions. A new negative scalenohedron (1*13"14*10) lies_close to 

 the zone of negative rhombohedrons between (0553) and 

 (0443). The planes are small but well developed and agree 

 fairly well with theory as to the measured angles. The letter 

 C has been assigned to this form. The forms observed on 

 crystals of this type are : — 



0(0001). #.(1011), \. (0887). £. (0443), v. (0553), 0.(0221), 

 B.(0551) L S.(O-ll-ll-l), pj_(1341), q i (2461), H: (3695) new, 

 M (8-4-12-5), and C (1-13-14-10) new. Fig. 2 shows this com- 

 bination. 



Type III. Crystals of this type are translucent, milky white 

 and average 20 mm in vertical length. They occur with consid- 

 erable amethystine quartz implanted in irregular aggregates on 

 the walls of partly filled seams in the diabase. In habit these 



