MYSORE PROVINCE, SOUTHliRN INDIA. 651 



as if he had been over the ground himself and had had tho benefit of 

 the analyses. 



Note on Specimens from Mysore, collected hy G. Attwood, Esq., 

 F.G.S. By Prof. T. G. Bonney, D.Sc., LL.D., F.R.S., F.G.S. 



1. Rock consisting of reddish garnets, very irregular in their 

 outline, in a greenish-grey crystalline matrix, with brown weathering. 

 Apparently a variety of eclogite. Microsc. : consists of garnet, quartz, 

 felspar, hornblende, iron-oxide, rutile (?),andafew grains of a honey- 

 yellow mineral. The garnet rarely shows a crystalline form ; often 

 it encloses grains of other minerals, chiefly quartz ; sometimes it forms 

 with them a kind of granular aggregate. The felspar is to a great 

 extent replaced by secondary products, but some small grains of 

 plagioclase are well preserved. One of the larger (rather decom- 

 posed) grains encloses quartz granules. The hornblende is green, 

 sometimes rather dark, showing very characteristic dichroism and 

 cleavage. The yellow mineral mentioned above is not abundant, 

 generally granular in form, but in one case prismatic ; here extinc- 

 tion seems to take place at a small angle with the larger edge. The 

 dichroism is not strong, and there is moderate chromatic polarization. 

 It may be a variety of epidote ; but I am uncertain. From the 

 general structure of the rock, it appears to me to have formerly under- 

 gone mechanical disturbance, but so long since that there has been 

 a practical recrystallization of constituents, i. e. very few distinct 

 indications of crushing now remain. The rock rather reminds me of 

 a variety of eclogite which I collected at Wahnapitae, on the Canada 

 Pacific railway. 



2. The rock in the hand-specimen appears to be a slightly foliated, 

 dark, hornblende-schist, containing some very small garnets. Under 

 the microscope it is seen to consist of green hornblende, quartz, 

 plagioclase felspar, garnets (very irregular in outline), haematite (?), 

 and a little biotite. The rock is now a hornblende-schist, but it is 

 by no means improbable that it may have once been an augitic rock 

 of igneous origin, modified by pressure and consequent mineral 

 changes. 



3. A flattened garnet in a fine-grained quartzose mica-schist. 

 Under the microscope more or less granular garnet is curiously 

 associated with clear, crystalline quartz and a little white mica, in a 

 way almost impossible to describe, but which may be understood 

 from the illustration. Parts of the slide are slightly stained with 

 limonite. I have no doubt this is from a garnet-bearing mica-schist, 

 which has been subsequently crushed and has then to a certain 

 extent recrystallized. 



4. A rather compact hornblende-schist. Under the microscope it 

 bears a general resemblance to No. 3, except that there is rather more 

 hornblende, less quartz, and the s])ecies of the felspar is less deter- 

 minate. The same remark applies to the following specimen : — 



5. A light-grey, crystalline, gneissoid rock. Under the microscope 

 it consists of quartz, felspar slightly decomposed, biotite (sometimes 



