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of Mr. Stephenson's slides, mounted in phosphorus dissolved in bisul- 

 phide of carbon, he found that there was nothing the matter with them, 

 although many of them had been mounted as long as 12 years ago. Had 

 there been any leakage there would, of course, have been a conflagration. 



Mr. Sturt said he had tried, with success, a mixture of styrax and 

 Canada Balsam, in which the Aulacodisci, Triceratium favus, and others, 

 showed up splendidly. This medium would be found a very good one for a 

 number of diatoms for which styrax alone was too highly refractive. 



The President said he had some little experience of styrax as a mounting 

 medium, althongh not as regarded the mounting of diatoms ; but his im- 

 pression was, from specimens which Dr. Gray had shown him, that when it 

 was obtained in a pure state it was a very admirable medium for mounting 

 a large proportion of diatoms. Dr. Gray had informed him that he actually 

 boiled the styrax upon the slide v\ ith the diatoms in it, so that apparently 

 the application of great heat did not always result in carbonizing. In his 

 own experience he had found it unsuitable, because the objects which he 

 desired to mount would not stand great heat, and on this account he had 

 been obliged to abandon it, althongh he had hoped it might be of great use 

 in mounting minute dissections of very clear chitinous objects, which were 

 otherwise somewhat difficult to see. As regarded the material itself, there 

 seemed to be no doubt that different samples varied in many respects to 

 such an extent as to give an impression that there must be more than one 

 species of plant from which it was obtained. One or two lots crystallized 

 all over the slides, whilst others did not show much tendency towards 

 crystallization ; but from whatever cause this difference might arise, it 

 seemed that the tendency to crystallize could be reduced to a minimum by 

 macerating the styrax in a succession of warm waters ; this was, however, 

 too troublesome for most persons to carry out. The styrax which gave the 

 crystals was much lighter in colour than the other kind, and on this 

 account, if it could have been obtained free from them, it would have 

 proved a more valuable medium. He had found that this light styrax was 

 extremely difficult to dissolve in any medium which would take up a large 

 quantity, so that when a mount did dry there was often very little of the 

 resin left under the cover-glass, rendering it necessary to frequently run 

 in more; and, on the whole, he found that it gave so much trouble that he 

 had to abandon it altogether. He must say, however, that for diatom 

 mounting where heat could be safely used it appeared to be a great advance 

 upon Canada Balsam. In the matter of mounting with phosphorus, it was 

 well known that Mr. Stephenson had been very successful, but it was un- 

 doubtedly very awkward stuff to handle by those who were inexperienced 

 in the art of using it. 



Mr. G. C. Karop read a translation of a paper from the German, relating 

 to a Parasite infesting the Diatomaceaa. The subject appeared to him to be 

 rather a new one, and, therefore, worth bringing before the Club, as it 

 would be interesting to know if anything of the kind had been seen in this 

 country. If those members who went to their excursions felt interested in 

 the matter, he thought they might find the subject to be one which 

 merited investigation. 



