462 Notices of Memoirs — C. E. Be Ranee. 



that tLe radiating projections with which these spheres are sur- 

 rounded were not siliceous spines like those of the Radiolarise, but 

 extensions of a continuous membrane which inclosed the entire 

 organism, and which, therefore, could not have the spicular nature 

 attributed to them. He then demonstrated that within this external 

 membrane is a second inner one, which latter is fitted with 

 numerous small vegetable cells like those shown to exist in the 

 interior of fossil spores and reproductive cryptogamous capsules, 

 found in the same beds as those which furnish the Traquarics. 

 These conditions are so different from those existing in any known 

 recent species of Eadiolarian as to lead Professor Williamson to 

 reject the idea of their Eadiolarian character. Their close organic 

 resemblance to some obviously vegetable conceptacles found in the 

 same Coal-measures suggest that the TraquaricB are also vegetable 

 structures. The Mountain Limestone deposits of some British 

 localities contain a vast multitude of minute calcareous organisms, 

 which Mr. J. W. Sollas and other observers regarded as Eadiolarians. 

 These. structures, however, seem to exhibit no satisfactory evidence 

 of being so. In the first place, these organisms are calcareous 

 instead of siliceous. It has been suggested that their siliceous 

 elements were removed and replaced by carbonate of lime, but this 

 appears to be most improbable. Professor Eoscoe and Professor 

 Schorlemmer agree in stating that they would require overwhelming 

 evidence before they would be prepared to accept such an explana- 

 tion of the present condition of these objects, or of the fact of the 

 substitution of carbonate of lime for silica, which such an explanation 

 renders necessary. Count Castracane has published ' an account of 

 a process by which he reduced numerous specimens of Coals to very 

 minute quantities of Coal-ash, and has stated that he found in these 

 ashes numerous marine and freshwater Diatomaceae. Professor 

 Eoscoe kindly allowed one of his ablest assistants in his laboratory 

 at Owens' College to prepare analyses of a number of Coals ac- 

 cording to Count Castracane's method. The residual ashes of these 

 preparations have been tested microscopically by Professor "William- 

 son, and in no one of them can a trace of a Diatom be found. 

 Beyond stating the fact, he is wholly unable to account for the 

 discrepancy between his results and those of the Italian observer. 

 So far as his present observations go, he finds himself compelled to 

 conclude that we have no proof of the existence of Eadiolarians or 

 of Diatomace^ in the British Carboniferous rocks. 



V. — Underground Waters.^ Potjrth Eeport of the Committee 

 ON Underground Waters in those Districts in England 



WISERE they are NOT AT PRESENT USED. By C. E. De EaNCE, 



E.G.S., Assoc. Inst. C.E. 



THE author referred to the great value of the maps of the 

 Government Geological Survey as a basis for the investigation 



1 See Geol. Mag. 1875, Decade II. Vol. II. p. 414. 



2 Eead before the British Association for the Adyancement of Science, Dublin, 

 16th August, 1878 (Section C). 



