THE TEREESTKIAL PERIDOTITES. — LHERZOLITE. 143 



A rock of similar cliaracter was obtained between Kimii and Kastrovolo, in middle 

 Euboea, possessing diallage instead of enstatite. The diallage is partly altered into a 

 greenish substance and partly into talc plates. 



A serpentine from Kumi was found to contain much chromite, magnetite, and some 

 green ouvarovite.* 



Oherlmif, Luzon, Philippine Islands. 



A dark blackish-green serpeutiae-like compact rock, with crystals of clear green dial- 

 lage and brownish enstatite. The principal cleavage planes show a mother-of-pearl 

 lustre. Microscopically the rock possessed the usual mesh structure, and contained mag- 

 netite and picotite.f 



Lizard District, Cormvall. 



The serpentines of this district were found to present intrusive relations to the 

 adjoining rocks by Prof T. G. Bonney. They send tongues and dikes into the latter and 

 hold included fragments of them, wliile the adjacent rocks at their junction with the 

 serpentine were often altered and contorted. The microscopic e.xamination indicated that 

 the serpentine resulted from the alteration of Iherzolite. The following is condensed 

 from Professor Bonney's description of the rocks and sections. The rock from Coverack 

 Cove is a dull mottled, red and green rock with flakes of a silky bronzitic mineral in the 

 green portion. Under tlie microscope the serpentine forms golden-colored and reddish- 

 and greenish-brown reticulated veins, which enclose colorless olivine, as well as augite, 

 enstatite, and diallage. Original and secondary iron ores occur. A rock from M\dlion 

 Cove has a similar composition and structure, but the alteration of the olivine has pro- 

 gressed further, with a differentiation of the common black ferruginous dust. A few 

 small grains resemble picotite. 



At Gue Graze a similar but more decomposed rock was obtained, which appeared to 

 contain a pseudomorphic product after feldspar. From the Lower Pradanach and the Pali 

 quarries similar rocks to that from MuUion Cove were obtained, but in one from Helston 

 Eoad a little hornblende was observed. 



The rock from Goomhilly Downs is a banded dull-colored light-greenish serpentine, 

 containing in the section, besides the serpentine, olivine, hornblende, luagnetite, and some 

 picotite. A number of other sections were examined, but tliey are mainly similar to the 

 above, or else have been more highly altered, so tliat the olivine was entirely changed ; 

 but the reader is referred to tlie original paper for the particulars^ 



Two other areas of serpentine were later examined in the Lizard district, one of which 

 shows excellent junctions and is clearly intrusive in the associated schist. Bonney also 

 re-examined the other portions of the district previously studied by him, and found the 

 strongest evidence of the intrusion of tlie serpentine into the associated sedimentary 

 rock. § 



From the Troad, Asia Minor. 



Owing to certain arrangements, and for a consideration, the lithological collection of 

 the Assos expedition has become the property of Professor Whitney, and passed over to 



* Min. Mittli., 1S7S (1), i. 477-4S5. 



t Kourad Oebbeke, Neues Jalir. Min., Beilage Band, 1S82, i. 499. 



t Quart. Jour. Geol. Soc, 1877, xsxiii. 884-928 ; 1883, ssxix. 21-23. 



§ Phil. Mag., 1882 (5), xiv. 478 ; Quart. Jour. Geol. Soc, 1883, xxxix. 21-23. 



