Revieiv of Recent Geological Literature. 177 
Some Analyses of Italiaii Volcanic Rocks. II. By Henry S. 
Washington. (Am. Jour. Sci., rjQ, 44-54.) 
I. Ciminyte. From a trachytic flow at Monti Cimino, Viterbo. 
The mineral components of this rock as coinputed from the analyses 
are orthoclase 37.9 per cent., labradorite 26.5, diopside 16.5, olivine 
17.3, and magnetite 1.8. This would place the rock between the 
trachytes and the andesytes and basalts in the group of andesitic 
trachytes or trachydolorytes of Rosenbusch (latyte of Ransome). 2. 
Selagyte. This is a lamprophyric latyte occurring as a volcanic neck 
in Tertiary marls, Monti Catini, Tuscany. The analyses are almost 
identical with those of ciminyte, though the diverse conditions of con- 
solidation have resulted in the formation of a different set of minerals; 
the selagyte carrying less olivine, orthoclase, and a plagioclase of less 
lime, but containing at the same time more augite and an abundance 
of biotite. It affords a good illustration of the tendency of the com- 
plex biotite molecule to crystallize as biotite in intrusions while it 
splits up into olivine, orthoclase, leucite, etc., in extrusions. Com- 
pared with biotite-vulsinyte, selagyte shows the additional presence of 
olivine, the available supply of MgO in the magma of the former be- 
ing exhausted by the crystallization of the biotite and augite. The 
chemical relations of selagyte to venanzyte, madupyte, wyomingyte, 
and orendyte are also discussed. 3. Andesyte. From a volcanic 
neck in Pliocene marls, Radicofani, Tuscany. The new analyses lead 
the author to consider the rocks examined as basic andesytes rather 
than ciminytes as he has previously held. 4. Leucityte. From a 
surface flow at Capo di Bove, Alban hills. Calculations based upon 
the analyses, aided by physical examination, give the probable min- 
eral composition as leucite 52 per cent., nephelite 10, mdilite 17, di- 
opside 17, and magnetite 4. Comparison is made between the compo- 
sition of the leucityte in question and that of Bearpaw Mt., Montana, 
and also with venanzyte. m. l. f. 
Geological Survey of Canada, Annual Report, {Neiv Series), Vol- 
ume X, i8g-/. George Dawson, Director. Including six Reports, 
separately paged, in total, xii, (046, and xxii (index) pages; with 8 maps, 
12 plates, and figures in the text. Ottawa, 1899. Price, 80 cents. 
The summary report of the director, with outlines of work done 
by field parties in 1897, fills 156 pages. The number of visitors to the 
museum during the year was 32,357; the appropriations for the sur- 
vey amounted to $117,675. 
William Mclnnes contributes the second part, "Report on the 
Geology of the area covered by the Seine River and Lake Sheban- 
dowan map-sheets, comprising portions of Rainy River and Thunder 
Bay districts, Ontario," 65 pages. Most of the field work of the Seine 
River tract had been done by the late W. H. C. Smith. The geologic 
formations, excepting the glacial and lacustrine surface deposits, are 
referred, in descending order, to the Animikie and Steep Rock series, 
the Keewatin, Coutchiching, and Laurentian. Granite-gneisses of the 
last named system occupy more than three-fourths of the entire area. 
