CLASSIFICATION OF IGNEOUS ROCKS 173 



Certain intrusive rocks in Banat, cutting through Hmestones 

 and crystalline schists, were named banatites by von Cotta.^ 

 They are usually quartz-bearing, and are intermediate between 

 quartz-diorites, quartz-augite-diorites, diorites, and augite-diorites. 

 Brogger^ applied the name to quartz-bearing monzonites, inter- 

 mediate between normal monzonites and adamellites, and related 

 to monzonites as quartz-syenites are to syenites. The extrusive 

 equivalent of banatite Brogger is quartz-trachyte-andesite 

 Brogger3 (see note under 229). 



Olivine-monzonite. While the Monzoni olivine- 

 monzonites carry basic plagioclase, elsewhere olivine-monzonites 

 with andesine are found. These rocks, therefore, fall in the 

 present subfamily. Kentallenite is stated by Hatch'' to be "iden- 

 tical with Brogger's olivine-monzonite The two feld- 

 spars are present in roughly equal proportions." As a matter 

 of fact, Hill and Kynaston^ distinctly state that "the term (mon- 

 zonite) has come to be associated with the presence of an approxi- 

 mately equal amount of the two feldspars — a feature which cannot 

 be said to be an essential characteristic of our group." From 

 the variation in the various specimens described, it would seem that 

 kentallenite is an olivine-orthoclase-plagioclase rock, the ratio of 

 the feldspars being quite variable, consequently not limited to 

 Family 13 here. 



Latite Ransom. The name latite, from the occurrence 

 of such rocks in the Italian province of Latium, was used by 

 Ransom^ for the extrusive equivalents of the monzonites. 



Syn. : Trachyte-andesite. (The term trachy-andesite 

 has been used in a different sense from trachyte-andesite by some 

 writers, though others make it synonymous. Rosenbusch^ uses 



^ B. von Cotta, Erzlagerstatten im Banat und in Serbien (Wien, 1864). 

 ^ W. C. Brogger, op. cit. (II, 1895), p. 61. 3 Jbid., p. 60. 



"• F. H. Hatch, The Petrology of the Igneous Rocks (London, i9i4),.pp. 206-7. 

 5 J. B. Hill and H. Kynaston, "On Kentallenite and Its Relation to Other Igneous 

 Rocks in Argyllshire," Quart. Jour. Geol. Soc., LVI (London, 1900), 532. 



^ F. Leslie Ransome, "Some Lava Flows of the Western Slope of the Sierra Nevada, 

 California," Amer. Jour. Sci., V (1898), 372. 



~' H. Rosenbusch, Mikroskopische Physiographie der masslgen Gesteine (Stuttgart, 

 1908), II, 1036-37. 



