565 



Mr. H. J. Quilter read a note " On a Method of Taking 

 Internal Casts of Foraminifera." 



Mr. Earland congratulated the author upon the remarkable 

 success which he had achieved, and expressed his belief that the 

 process would be one of great value to the student. Natural 

 casts had been very largely used in the study of structure by 

 Carpenter and others ; but natural casts were often not available, 

 and they were also very delicate and difficult objects to prepare, 

 and seldom as perfect as the specimens exhibited by Mr. Quilter. 

 But these natural infiltrations or casts were much more enduring 

 than the calcareous shells of the forams, and were found in 

 a more or less perfect state in many strata from which the 

 actual Foraminifera had entirely disappeared. The earliest 

 recorded Foraminifera were those of the Lower Cambrian clays 

 of Russia and the Lower Cambrian sandstones of Shropshire, 

 and these were all glauconitic casts, and showed a considerable 

 diversity of form, even at this very ancient period. Similar 

 glauconitic casts were being formed at the present time on the 

 sea bottom round many of the Continental areas ; but the 

 chemistry of theii' formation was not clearly understood. He 

 hoped that Mr. Quilter would continue his experiments, and 

 endeavour to obtain a mineral infiltration, as this would be an 

 improvement on wax casts. 



Mr. W. J. Stokes said that the perforations in diatoms had 

 been demonstrated by means of infiltrating them with mercury 

 and silver salts, and suggested that similar methods might prove 

 successful with Foraminifera. 



Mr. Morland said he had with him a slide of diatoms which 

 had been filled up in this manner, the only fault being that 

 they generally got so much filled up that the detail was quite 

 blotted out — because when the salt was added to the solution 

 the precipitate came down in such a quantity that the diatoms 

 were quite obliterated, Mr. Haughton Gill read a paper on 

 the subject some years ago, which was published in the R..M.S. 

 Journal. 



Mr. Earland did not think this process was at all likely to be 

 of use in the matter, because in the case of diatoms they were 

 filling up perforations with a fine precipitate, and not obtainiag, 

 nor desiring to obtain, solid casts. 



Mr. Wesche said he knew very little about Foraminifera, but 



