I14 NEW YORK STATE MUSEUM 
b:of the principal type. This form appears as a series of well developed 
planes having none of the vicinal characters which mark the development 
of b:of the principal type. The scalenohedron H: (3142) occurs as a series 
of narrow faces between K:andp. Traces of the characteristic twinning 
which mark the crystals of the principal type are here noted; the twinning 
tendency is, however, very weak and only finds expression in an occasional 
shallow reentering “ gash.” 
The interesting zonal relations of the occurring forms are shown in the 
stereographic projection [plate 22]. 
SUMMARY OF MEASURED AND CALCULATED ANGLES 
NO. OF 
LETTER ANGLE Be ae MEASURED | CALCULATED 
° , | co} / 
OQ, 8 tam, 1012 : 4041 3 77 584 | 77 58 
3 iq. 1012 : 7071 2 72 On ee a 
Os 210 1012 : 1010 2 64 12 63 45 
O 3 @, IE 2 O44 Wh. 1 59 46 59 36 
es 4156 : 4516 i 54 9 54 i 
e:ie: 4156 : 5146 1 13 IPA) ils} 5 
loseanlor: 7189 = 7819 1 61 34 61 BD 
ioe 8 log 7189 : 8179 2 8 32 8 23 
joe 210% 7189 : 1789 1 rial 34 71 37 
lake eke BAD 2 Dwr 3 9 22 9 Oil 
Keke DBL -g DRI 2%, UD 7 75 Do 
Keele PAB 2 Biwi 1 35 42 35 36 
Ke IK PBL 2 WABI iL 46 Si 47 14 
p: : p: 1341: 1431 1 26 Hil 26 444 
We 3 WE 1@,4), 1.3 2 1 210.3 2 31 13 31 16 
Us 2.12 NO) 28, MES 3 4b, 1); 12.8 1 38 35 38 49 
AyearR 4261 : 6241 1 38 Ne 37 30 
Th os 4261 : 6281 2 6 23 5 54 
9: 9.4.13.2 :13.4.9.2 3 34) 20 Fok 25 
9:8 9.4.13.2:4.9.13.2 1 Seo oy MH Sn 55 
Oy 3 AR @).4, 13,2 9 8,44, 19.1 1 4 43 4 47 
) 3 S36 ©) 4 13,2 2 GBS 3 3 59 4 6 
S: +. 6281 : 7071 6 Ne AG Te 453 
yee Gye 6281 : 268T 1 35 53 35 52 
Sy 2 saa, 6281 : 4041 2 15 S) 14 59 
(ae Sk Q 4b Wi 2 iD.4.8. 1 2 37 o7s | 38 2 
(ie 3 soa 8.4.12.1 : 4041 2 20 43 20 444 
