306 Review of Recent Geological Literature. 
visions proposed by Rosenbusch, followed by an extended table, giving 
in condensed form, the subdivisions of Rosenbusch, the structures ob- 
served, the order of consolidation of the constituent elements, and the 
equivalent names of Fouque and Levy. At the end is a table giving 
the correspondence of the granitoid and trachytoid or porphyric rocks, 
according to the classification of MM. Fouque and Levy, with the cor- 
responding names of Rosenbusch. The dominant idea of Professor 
Rosenbusch has been, according to M. Levy, to constitute natural 
groups both petrographic and geologic. He has thus substituted the 
notion of mode of formation {mode de glsement) for the more positive 
and more relevant datum of structure. It is thus that across his three 
grand subdivisions of mode of formation — depth, dikes andeffusives, he 
has sought to group, not associations chemically or mineralogically 
analogous, but those which he believed derived from each other by 
way of ramifications. It is a classification based on hypotheses, and 
in its ultimate consequences is not followed cut by its author himself. 
The founders of the French school deem it necessary to base their 
classification and nomenclature of the rocks on facts, independent of 
every hypothesis, and positive in their nature. Modern petrography, 
they say, employs means sufficient for attaining this end without hesi- 
tation. There is general accord in reference to the principal stuctures 
of associations of minerals and rocks ; and we know how to determine 
these minerals Avith precision. It is therefore exclusively to the struc- 
ture of association, and to mineral composition that they persist in 
addressing themselves in the attempt to classify and name the rocks.* 
Sketch of the Geology of Nerv Zealand. By Capt. F. W. Hutton. 
(From the Q. J. G. Soc London, May, 1883, pp. 191-220.) This mem- 
oir is the only published source of information on all portions of the 
colony of New Zealand. The islands have been studied for the last 
thirty years. Valuable contributions to their geology have been made 
by Dr. Hochstetter, Dr. Hector and the geological surveys ; but up to 
the date of captain Hutton's memoir, no one had attempted to describe 
the geology of New Zealand as a whole. The geology of the region is 
remarkably diversified. Sedimentary rocks of almost all ages are rep- 
resented, from Arch.iean upward, and all but the lowest have yielded 
fossils. There are metamorphic and eruptive rocks. There are vol- 
canic cones of every magnitude, up to Ruap^hu, more than 9000 feet in 
hight, and they are presented in all stages of degradation, from mere 
* The leading authorities of the French school are as follows : Min- 
^ralogie micrographique. Introduction a I'^tude des roches eruptives 
fran^aises, par F. Fouqui^ et A. Michel L^vy, 4to, 2 vols, text and 
plates, Paris, 1S79. Cours de min^ralogie, par A. de Lapparent, 8vo. 
pp. 560, with 519 cuts in the text, and a chromolithographic plate, 
Paris, 1888. A new edition for 1890 is announced, which wo have not 
seen. Les min^raux des roches. 1. Application des m^thodes min(5- 
ralogiques et chimiqnes a leur 6tude microscopique, par A. Michel 
L6vy. 2. Donnees physiques et optiques, par A. Michel Lt^vy et Alf. 
Lacroix, Paris, 1888, 8vo. pp. 334. Trait6 de crystallographie g^omet- 
rique et physique, par E. Mallard, Paris, 1879. 
