3338 The American Naturalist. [September, 
the salt pampas of that country. Osann” has recently studied three 
of these minerals crystallographically and optically. Some of his re- 
sults are summarized below: 
Darapskite (Na,SO,+H,O, Dietze) from Pampa del Toro near 
Pampa, where it occurs abundantly with blédite. Monoclinic with 
axial ratio a: b: ¢ = 1.5258: 1: 0.7514. p = 77°5’. Habit tabular 
parallel to the orthopinacoid. The observed forms were (100), (001), 
(010), (110), (101), (201), (101), (302), (011), (111), (111), and (121). 
Twins are common according to (100), and are sometimes polysyn- 
thetic. H, 2-3, G, 2.203. Easily soluble in water. 
Lautarite 4 Ca(1IO,),, Dietze +} from Calcium Chloride Pampas, 
also Pampa del Pique III and in Pampa Grove. Monoclinic with 
axial ratio a: 6: e= 0.6331 : 1 : 0.6462. @ =.73°38’.. The prismatic 
crystals show the following forms: (110), (120), (010), (001), (011), 
(101) and (101). Cleavage parallel to (011). The crystals vary from 
colorless to bright wine-yellow, and are difficultly soluble in water. 
H, 3-4, G, 4.59 (Dietze). 
Dietzite. This mineral occurs in the Chloride of Calcium Pampas, and 
was determined by Dietze to have the formula 7 Ca (IO,), 8 Ca Cr O, 
It has monoclinic symmetry with axial ratio a: b: e = 1.3826 
0.9515. 2 = 73°28’. Crystals tabular according to 100, possessing 
the forms: (100), (010), (001), (110), (210), (101), (221) and (223). 
H, 3-4, G, 3.698. Soluble in hot, but only slightly soluble in cold, 
water. The mineral is named by Osann in honor of the finder, Dr. 
Dietze, who perished in a snow storm while on a scientific expedition in 
the Andes. Lautarite and Dietzite are interesting as being the first 
salts of iodic acid that have been found in the mineral world. 
Miscellaneous.—Rinne" determines the symmetry of crystals of 
metallic aluminium to be probably isometric from a study of quite per- 
fect growth forms. Lacroix” describes well crystallized epidote from 
or near Voheimar, Madagascar, which have developed the base, ortho- 
pinacoid, the unit positive orthodome, and also (210), (102), (011) and 
(111). He also makes a correction to his earlier paper on the pyro- 
morphite of New Calidonia, adding the form (1121) and replacing the 
described forms (5054) and (10.0.10.1) by the forms (15.0.15.14) and 
(9091). Ussing,“ in connection with a mineralogical-petrographical 
 Thidem, 23, pp. 584-589, pl. 7 (1894). 
! Neues Jahrbuch f. Min., etc., 1894, IT, pp. 1-2. 
© Bull. Soc. Franç Min., xvii, pp. 119-120, May, 1894. 
'SThidem, pp. 120-12 
MMfineralagiekopetsumriliske Undersogelser af Gronlandske Nefelinsyeniter og 
beslaegtede Bjaergarter, by N. V. Ussing, pp. 220, pls. 7, 1894. 
