452 RECORD OF SCIENCE FOR 1886 



fill field for the discovery of new forms. Notwithstanding the large 

 number of planes already credited to the species, the labors of N. vou 

 Kokscharow, jr., and Des Cloizeaux have resulted in adding many new 

 ones to the list, some of them of complex symbols. The calculated 

 angles for all these forms are given in the concluding part of vol. ix of 

 the Miueralogie Easslands, already alluded to. Ailing has measured 

 tlie unusually perfect colorless topaz crystals from Utah and found 

 them to agree closely iu their elements with the Uralian crystals. Des 

 Cloizoaux has extended his study of the vanadate bearing his name 

 (descloizite) and proved conclusively on optical grounds that it is ortho- 

 rhombic, not monoclinic in crystallization. Huntington has investi- 

 gated the crystalline structure of native iron as shown by cleavage frag- 

 ments and etched sections of meteorites, and has extended and devel- 

 0})ed our knowledge of that important subject. 



Several iiapers have been published devoted to a crystallographic 

 study of some American species. The phenacite from Florissant, Col- 

 orado, is described by Des Cloizeaux with figures representing a new 

 form, Penfield has described complex cr^ stals of brookite from Magnet 

 Cove, Arkansas, and the writer of this report has continued the same 

 subject, showing the unusual variety in form of the crystals from this 

 locality ; the latter work was based upon the tine suite of crystals in 

 the collection of Mr. C. S. Bement, of Philadelphia. The Bement col- 

 lection has also given, iu the hands of the writer, material for an ex- 

 tended memoir on the crystallization of native copper of Lake Superior. 

 The specimens from this locality are remarkably complex in form, espe- 

 cially in the twinning groups, and a series of some sixty figures in four 

 plates were needed to illustrate the different forms. Another paper is 

 devoted to the crystallization of gold from California and Oregon, and 

 others to columbite, diaspore, etc. 



The minerals from Alexander County, North Carolina, brought to 

 liglit by the explorations of W. E. Hidden, have been crystallograph- 

 ically studied by vom Hath. The monazite has been figured and meas- 

 ured, more particularly the nearly symmetrical cruciform twins, with 

 the orthopinacoid as the twinning plane, also described by Hidden. The 

 spodumenc (hiddenite) has been measured also, and has yielded a con- 

 siderable number of new j^laues ; the same is true of the quartz which 

 has proved to be remarkably rich in interesting points. The locality 

 has furnished, among other things, a few crystals showing the rare basal 

 plane as noted by Hidden and Des Cloizeaux. The beryl is, too, excep- 

 tionally fine in crystallization, and having, as illustrated by vom Kath, 

 a novelty and complexity of form surpassing the Uralian specimens. 

 The same author has measured the North Carolina rutileaud xeuotime. 

 The vanadinite of Arizoua and New Mexico has been shown by Penfield 

 to be highly complex in form, and to exhibit the pyramidal hemihedrism 

 of the group with unusual distinctness for this S])ecies. 



Iu the broader subject of physical mineralogy a large number of im- 



