XX ' OBITUARY NOTICES. 



bladed masses of a gray, bluish-white and blue cyanite ; a yellowish- 

 white micaceous mineral occurring where the blades meet, em- 

 bedded in which is diaspore containing in immediate contact with 

 the cyanite a rounded fragment of a slightly pink corundum. 



The list of these associated minerals includes staurolite, pyro- 

 phylite, damourite, ephesite, jerTerisite, chlorite, margarite and lazu- 

 lite, among others ; and in the paper are described four new min- 

 erals : kerrite, maconite, willcoxite and dudleyite. 



The conclusions reached by Dr. Genth as the result of this elabo- 

 rate investigation are as follows: (i) At the period when the 

 chromiferous and chrysolite beds were deposited a large quantity 

 of alumina was separated and formed beds of corundum; (2) this 

 corundum has subsequently been acted on, and in this way changed 

 into various mineral species — spinel, fibrolite, cyanite, tourmaline, 

 damourite, chlorite and margarite, and, perhaps, also into some 

 varieties of feldspar ; (3) a part of the products of the alteration 

 of corundum still exist in the form of large beds of mica and 

 chlorite slates or schists ; (4) another part has been still farther 

 altered and converted into other minerals and rocks, such as pyro- 

 phyllite, paragonite, beauxite, lazulite, etc. 



Dr. Genth gave some attention also to the chemistry of meteor- 

 ites. In 1854, he described a meteorite from New Mexico, given 

 to him by Prof. Henry, and labeled " native iron." It afforded 

 on analysis: iron, 96.17; nickel, 3.07; cobalt, 0.42, and insoluble 

 matter, 0.57, this latter consisting of iron, nickel and titanium. 

 The following year he published the analysis of a fragment of one 

 of the meteoric irons of Tucson, Mexico, presented to the Acad- 

 emy of Natural Sciences by Dr. Herrmann. This analysis showed 

 the meteorite to consist of iron, copper, cobalt, nickel, chromium, 

 alumina, magnesia, lime, soda, potash, phosphorus and silica, 

 together with a feldspathic mineral, supposed to be labradorite. It 

 agrees substantially with analysis by J. L. Smith of a fragment cut 

 from one of the huge masses in that region by Lieut. John G. 

 Parke, U. S. Engineers. A third meteoric iron was described by 

 Dr. Genth, in 1886, from East Tennessee. 



In 1874, Prof. Lesley, Director of the Second Geological Survey 

 of Pennsylvania, appointed Dr. Genth Chemist and Mineralogist 

 of the Survey. His acquaintance with the subject committed to 

 him is well shown by the fact that before the close of that year he 

 presented a "Preliminary Report on the Mineralogy of Pennsylva- 



