Geology and Natural History. 153 



are described in detail and a full account given of the augite- 

 andesites and other igneous rocks. The system of exploitation is 

 then discussed and the various metallurgical processes by which 

 the metals are obtained from the ores. In the preparation of this 

 volume the Director, J. G. Aguilera, has been ably seconded by 

 E. Ordonez, I. O. Gonzalez, P. C. Sanchez and others. 



5. Zirkeiite : A question of Priority ; by Dr. M. E. Wads- 

 worth. (Communicated.) — In the Mineralogical Magazine, Vol. 

 xi, pp. 86-88 (read June 18, 1895) is described a mineral con- 

 taining zirconium, titanium, lime, iron, etc., under the name of 

 zirkeiite. This paper was prepared by my friend, Dr. E. Hussak, 

 and by Mr. G. T. Prior. Later Mr. Prior (1. c. pp. 180-183, 

 read Nov. 17, 1896) published an analysis of the same mineral. 



I wish to protest against the use of the name zirkeiite for this 

 mineral on the ground of the prior use of it to designate a com- 

 monly-occurring rock belonging to the basaltic family. When 

 two subjects are so intimately connected as mineralogy and pe- 

 trography it does not seem to be for the interest of science that 

 names should be duplicated in them. So true is this that I aban- 

 doned the name rosenbuschite, which I had given to a class of 

 rocks in honor of Professor Rosenbusch, because only a few weeks 

 previously it had been employed to designate a new mineral. 



The term zirkeiite was used by me in 1887, or seven years before 

 it was taken by Messrs. Hussak and Prior. (See Preliminary 

 Description of the Peridotites, Gabbros, Diabases and Andesites 

 of Minnesota. Bulletin No. 2. Geological Survey of Minnesota, 

 1887, pp. 30-32.) It was used to designate the commonly-occur- 

 ing altered conditions of basaltic glassy lavas which are often 

 called diabase glass, etc. Zirkeiite occurs forming the entire mass 

 of thin dikes, and the exterior parts of many dikes of diabase and 

 melaphyr, as well as the surface of old lava flows like the mela- 

 phyrs and diabases of Lake Supeiior, Newfoundland and else- 

 where. Zirkeiite holds the same relation to tachylite that diabase 

 and melaphyr do to basalt, i. e. an older and altered type. The 

 macroscopic and microscopic characters of this rock were given 

 in the place cited above. 



The term zirkeiite was again used in the same way in my 

 Report of the Geological Survey of Michigan for 1891-1892; 

 (1893, pp. 90, 97, 138, etc.) It was also published in my classifi- 

 cation ot rocks given in the Catalogue of the Michigan College ol 

 Mines (Michigan Mining School), 1891-1892, p. 104; 1892-1894, 

 Table XI; 1894-1896, Table XI. Further the term zirkeiite is 

 defined in accordance with my usage in Lcewinson-Lessing's 

 Petrographisches Lexikon, 1893, p. 252 ; and accounts of it are 

 given in the Neues Jahrbuch iiir Mineralogie, 1893, II, p. 292, 

 and in Kemp's Handbook ol Rocks, 1896, p. 170. 



Michigan College of Mines, Houghton, Mich, Dec. 17, 1897. 



6. Ifrystaltofjrrrphisehe Winkeltabellen ; by Victor Gold- 

 schmidt, large 8°, 432 pp. Berlin, 1897 (Julius Springer). — In 

 this work is presented for the first time a complete table of 



