1890.] Mineralogy and Petrography. 71 
described, and very fine pictures of the structures are given. Without 
being able to enter into a full discussion of the points so clearly 
brought out by Mr. Iddings, it is interesting to note that he regards 
the lithophysz as having been produced, after the partial solidification 
of the rock in which they occur, by the expansion of the vapors im- 
prisoned within the rock-mass before its eruption. The formation of 
the minerals coating the walls of the cavities was caused by the action 
of this water upon the materials of the rock. The expansion of the 
vapors was due to the diminution of the pressure under which they 
were confined in consequence of the upward bending of the rock 
layers above the places now occupied by the lithophyse. These con- 
clusions are in direct opposition to those of Szabo, Roth, Zirkel, and 
Cole,5 who regard lithophyse as resulting from the alteration of 
spherulites. A nephelinite composed of a granular aggregate of 
nepheline cementing porphyritic crystals of olivine, shreds of biotite, 
microlites of augite and magnetite, is announced by Levy and Callot * 
as existing in a boss near Rougiers in Var, France. 

New Minerals.— 7¢phrowillemite.-—Dr. Koenig’? communicates 
the discovery of a brownish-gray, resinous, infusible substance at the 
Trotter Mine, Franklin, N. J. Only a portion of a single mineral 
was obtained, which yielded on analysis : 
SiO, = 27.75, ZnO = 60.61, MnO = 10.04, Fe,O, = 1.80, CaO = tr. 
It is a manganese willemite with the formula (ZnMnFe), SiO,. De- 
Saulesite.—Associated with the above-described mineral, and also with 
sphalerite, chloanthite, fluorite, apatite and nicolite, beneath a Stratum of 
yellow garnet, at a depth of 340 feet from the surface, is a greenish 
substance encrusting fluorite and filling cavities in it. In the closed 
tube it yields water and turns brown. It is infusible before the blow- 
pipe, but at this high temperature it regains its original color. Its 
composition is: 
SiO, NiO ZnO FeO CaO TE os H,O at 100° H,O at 600° 
3ï. 62 38.22 4.00 2.03 .70 9-44 7.14 
corresponding to NiZnFe (siO,) if = ie It is therefore a nickel- 
iferous garnierite, Yitrialite—From the gadolinite locality in Llano 
County, Texas, five miles south of Bluffton, Messrs. Hidden and 
Mackintosh ê have discovered a very large number of new and fare 


5 AMER. NATURALIST, Jan., 1887, p- 70. 
6 Comptes Rendus, 1889, p. 1124. 
1 Proc. Acad. Nat. Sciences, Phila., Pt. II, 1889, p. 184. 
8 Amer. Jour. Sci., Dec. 1889, p. 474. 
