352 RECORD OF SCIENCE FOR 1887 AND 1888. 



PosEPNY, F. Ueber die Arlinoleu vou Pribram in BiJhmeu. Miu. uud pet. Mittheilim- 

 geu, 1888, X. Baud, iii. Heft, p. 175. 



Raisin, Cathekine A. Notes ou the Metaiuorphic Rocks of South Devou. Quar. 

 Jour. Geol. Soc., No. 172, November, 1887, vol. XLiii, p. 715. 



Ou some rock specimens from Somali Land. Geol. Mag., September, 1888, 



p. 414. 



Describes these rocks as porphyrites, horublende diabase, granite, gneisses, 

 talc schists, epidote schists, quartzite, grits, saud and lime stones. 



Ou some rock specimens from Socotra. Geol. Mag., November, 1888, p. 



504. 



ROWE, A. W. On the rocks of Essex Drift. Quar. Jonr. Geol. Soc, No. 171, August, 

 1888, vol. XLiii, p. 351. 



The rocks were studied with a vievs', if possible, of ascertaining their original 

 source. They are identified as granite syeuite, quartz porphyries, quartz tra- 

 chytes, trachytes, dolerites, grauulites, crystalline schif:ts, quartzites and quartz 

 rocks, sandstones, limestones, and fragments of silicified woods. 



Rudolph, Fritz. Beitrag zur Petrogi-aphie der Andeu vou Peru uud Bolivia. Miu, 

 uud pet. Mittheiluugen, ix. Band, iv. u. v. Heft, p. 2()9 

 The rocks described are audesites of the pyroxene or hornblende varieties. 



RuTLEY, Frank. Ou Perlitic Felsites, etc. Quar. .Tour. Geol. Soc, No. 176, Novem- 

 ber, 1888, vol. XLiv, p. 740. 



Describes au obscure perlitic structure occurring in certain felsitic rocks of the 

 Herefordshire Beacon; suggests, further, the probability that felsites resulting 

 from the devitrification of obsidian, quartz felsites, aplite, arkose or feldspathic 

 grits may on decomposition pass into rocks composed mainly of (juartz and kaolin 

 and thence by further alteration into epidosite. 



Ou the rocks of the Malvern Hills. Quar. Geol. Jour. Soc, No. 171, August, 



1888, vol. XLIII, p. 481. 



Sandberger, F. Benierkuugeu iiber den Silbergehalt des Glimmers aus dom 

 Gueisse von Schapbach uud des Augits aus dem Diabase von Andreasberg am 

 Harze. Neues Jahrb. Miu., Geol., etc., 1887, i. Band, erstes Heft, p. HI. 



Sauek, a. Ueber Riebeckit, ein neues Glied der Hornbleudegruppe, sowie iiber Neu- 

 bildung von Albit in granitischen Orthoklasen. Zeitschrift dents, geol. Gesell., 

 XL. Band, i. Heft, p. 138. 



Schmidt, C. Diabasporphyrite und Melaphyre vom Nordabhang der Schweizer 

 Alpen. Neues Jahib. Miu., Geol., etc., 1887, i. Band, erstes Heft, p. 58. 



Describes a diabase |)orphyrite and melaphyr presenting certain interesting 

 features. The porphyrite occurs, cutting Eocene strata in its three typical varie- 

 ties, as a dense, dirty, grayish green, in places dark violet mottled or A'eined rock 

 carrying small nests of calcite. In the thin section it is pronouncedly porphyritic, 

 with long, slender plagioclases, which from their small extinction angles are sup- 

 posed to be oligoclase. The groundmass consists of augite and feldspars, some- 

 times grouped in tuft's or with a tendency toward spherulitic structure. The 

 feldspars contain inclosures of the amorphous base, often showing a mere vein 

 of feldspar substance. The second variety is of a gray green color, and badly 

 altered, only the feldspars being recognizable while the base has gone over to 

 chloritic material, and granules of opacite, calcite, and chlorite abound. The third 

 variety is a reddish brown dense rock which the microscope shows to consist of a 

 confused aggregate of oligoclase leistens with interstitial irregularity developed 

 augites. The stone therefore presents all the characters of the pre-Tertiary por- 

 phyrites, although, as above iu)ted, of post-Eocene age. The melaphyr is also of 

 interest as containing olivine, which has undergone alteration iuto a bastite-like 

 substance, hero noted for the lirst time. 



Ueber den sog(uiauiiten Taveyannaz-Sandstein. Neues Jahrb, Miu., Geol., 



etc., 1888, II. Band, erstes Heft, p. »0. 



