Geology and Natural History. 61 
_ Journals since the issue of the Mineralogy in 1868; these refer- 
ences are placed under the name of each species, "to which the 
article relates, the species pfs arranged alphabetically. This 
Appendix is consequently an index to all the mineralogical litera- 
ture of the past seven ani list of mineralogical books and 
8, 
, tions, V., by Prof. C. Kiem, in 
Heidelberg.—Prof. Klein has investigated with great minuteness 
the crystals of octahedrite (anatase) from the Binnenthal. He 
¢Ds 
10, On the presence of Vanadium in roeks,—Dr. A. A. pages in 
a paper read before the American Academy of Sciences, Boston, 
in January last, states that he had detected vanadium in many 
rocks associated usually with — ounds of phosphorus and of 
manganese. His mode of examination for the detection of vana- 
rocks are presented. The author proposes in a future 
give a tabulated list of the nse le also states the idee aie 
Bost 
= retained, though the luster of the planes is gone. They were 
ound to be twins in all cases, the several laws of twinning being 
ee a to those often observed in orthoclase. Sometimes the 
crystals are very complex, rig made up of a number of individ- 
uals. They have a snow white or sometimes yellowish color and 
earthy fracture, sou though firm in the fingers are easily ground 
in the mortar to a soft, white powder. An analysis gave Sipécz: 
Si 55-96, 41 31-34, eg 116, a 1-73, a 0-65, Na 0-18, Ka 4-96, H 5-41=101-39 
nder the peta ages mass is seen to consist of two kinds 
ig some anbhan ed feldspar, eed wis. prese nt in anal quan- 
tities, Professor Tschermak finds that the remainder corresponds to 
the formals, 3Si, Al, H, which ‘ regards 8 as expressing the composi- 
tion of the d to, it being thus a hydrous 
alumina silicate differing from kaolinite. The change which has 
place in the original material consists essentially in an 
r sBip ; lo 
Mitth., 1874, iv, p. 269. E. ge 
