PF/rRO(;HAPHv. 339 



that andaliisitc, a juiiieial cousideicd as iionnally a ])ro(lu('t of con- 

 tact inctaiiioi-i)liisiu in tho crystalliiu' S(!hists, is iii niici()sco[)ic I'ornis 

 a by no means rare constituent of the true, granites. Williams* de- 

 scribes for tiie lirst time in this country the presence of pleoinist (her- 

 cynitoj as occurring in the noriles of the Hudson River rejrion, Xew 

 York, and also perowskite as a microscopic constituent of Ilu> altered 

 jteridotite at Syracuse, in the same State- A more interesting discov- 

 ery than any of the above is that of the occurrence of leucite, hitherto 

 found only in recent lavas, in some paleozoic eruptions of Brazil, as an- 

 nounced by Derby. f Schmidt has noted for the first time the altera- 

 tion of olivine in a melaphyr from the Swiss .All)S into a bastitelike 

 substance. AYilliams | has noted the occurrence of rutile secondary 

 after ilmeuite in a decomposed diabase from the Big Quinnesec Falls 

 of the Menominee Kiver, Wisconsin. That, however, these are in fact 

 alteration products Cathrein denies. § Tliis last-named autliority has 

 also described || an interesting (iase of the occurrence of plagioclase 

 pseudomorphous after garnets in a, garnet ainphibolito from the Swiss 

 Alps. The mineral cordierite, as an essential constituent of rock 

 masses, has for the first time in America been observed by Hovey^] in 

 a gneiss occurring near Guilford, Connecticut. 



The se«ondary enlargement of the mineral ]>articles of fragmental 

 rocks as desmibed by Tornebolim, Sorbv, Irving, and Van llise, lias be- 

 come a matter of almost daily obser\ati()n. Such growths are not, 

 however, contiued to clastic rocks. Becke has described a case of sec- 

 ondary enlargements of the hornblende in massive eruptive rocks, and 

 Van Ilise ** has described a like secondary growth of hornblende upon 

 both hornblende and angites in certain Wisconsin diabases. Lastly, 

 the present writer has described ft a case of the secondary enlargement 

 of angites by fresh dei)osition of augitic material in a peridotite from 

 Little Deer Isle, on the coast of Maine. 



NKCKOLOGY. 



The science has suffered greatly through the deaths of Dr. 'Mux 

 Schuster, of the University of Vienna; of Prof. II. I), h-ving, IJ. S. 

 CTeologi(;al Survey, Madison, \Visconsin ; of Vrof. II. Carvill Lewis, 

 Philadelphia. Pennsylvania., and Dr. Tiu'odor Kjerulf. of Christ iania, 

 Korwav. 



*Nenes Jabrb., 1887, ii 13., \). 2(37. 

 tQiiar. .Jour. Geol. Soc, 1887, Vol. xi.iii, N'o. 171. 

 tNciics Jaliib., 1887, li J?., ]>. 2(y.\. 

 ^ Ibid., 1888, II B., 2 Heft, p. l.')l. 

 WlbiiL, 1887, iB., 2 H., p. 147. 

 HAni. Jour. Sci., .July, 1888, j). i'>7. 

 *" Ihhl. May, 1887, p. 385. 

 ]Uhid., Juuc, 1888, p. 488; also I'n.r. U. S. Nat. Mus., isss, p. I'Jl. 



