Intelligence and Miscellaneous Articles. 243 



Microlestes or to Plagiaulax cannot be determined ; Mr. Dawkins has 

 therefore named it provisionally Hypsiprymnopsis Rhaticus. In con- 

 clusion he traced the range of the Marsupials in space and time, 

 showing that of the six families into which Van der Hoeven divides the 

 existing Marsupials, two — the entomophagous and sarcophagous 

 Dasyurina, and the phytophagous Macropoda— had been repre- 

 sented in England during the interval between the deposition of 

 the Purbeck beds and that of the Rhaetic Marlstones below the 

 Bone-bed. 



2. " On the Geological Structure of the Malvern Hills and ad- 

 jacent District." By Harvey B. Holl, M.D., F.G.S. 



The object of this communication was threefold, namely (1) to 

 discuss the structure and origin of the crystalline rocks of the Mal- 

 vern Hills, (2) to give the results of an examination of the super- 

 posed Palaeozoic strata, (3) to state the chronological relationship 

 of the several events in their geological history. 



The geological structure of these hills was described in detail, 

 and it was concluded that the rocks hitherto treated of as syenite, 

 and supposed to form the axis of the range, are in reality of meta- 

 morphic origin, consisting of gneiss (both micaceous and horn- 

 blendic), mica-schist, hornblende-schist, &c, all invaded by vein of 

 granite and trap-rocks. It was then shown that the Hollybush 

 Sandstone is the equivalent of the Middle Lingula-flags, and that 

 the overlying black shales correspond with the Upper Lmgula-beds, 

 the whole being overlain, as in Wales, by Dictyonema-shales. These 

 rocks, on the east of the Herefordshire Beacon, are altered by trap- 

 dykes, which were shown to be of later date than those traversing 

 the crystalline rocks before alluded to. Allusion was next made to 

 the Upper Llandovery strata which overlie unconformably the primor- 

 dial rocks just noticed, after which the several faults in the district 

 were described in detail. 



Dr. Holl concluded with some remarks on the general relations of 

 the rocks of the Malvern Hills with those of the surrounding dis- 

 tricts, describing the successive physical changes supposed to have 

 been consequent upon their deposition and their subsequent eleva- 

 tions and depressions. 



XXVIII. Intelligence and Miscellaneous Articles. 



ON THE ROTATORY POWER OF ACTIVE LIQUIDS AND OF THEIR 

 VAPOURS. BY M. D. GERNEZ. 



WHEN Biot, in 1815, was accidentally led to the discovery of ro- 

 tatory polarization in liquids, he soon recognized in this re- 

 markable phenomenon all the characters of a property depending on 

 the individual form of the molecules. Among the experiments which 

 he devised to exhibit this phenomenon, the best consisted in volati- 

 lizing an active liquid (oil of turpentine) and causing a ray of pola- 



