SCIENCE- GOSSIP. 



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■exposed to the weather, and a number of little 

 white patches collected in the hollows. These 

 were seen to contain foraminifera, chiefly large 

 Miliolinae ; so I collected enough to fill a two- 

 ounce tobacco tin nearly. The i'oraminifera would 

 not float in water, but by rocking successive por- 

 tions in a soup-plate, and then rocking again, and 

 finally rocking more gently to separate the vege- 

 table debris, a nearly pure gathering was obtamed, 

 mixed with a small percentage of fragments of 

 shells and a few " blacks " composed of coal or 

 coke dust, soot, etc. In mounting spread slides I 

 picked out most of the blacks without a hand lens, 

 using a fine brush, and placing the spread slide or 

 cover on a white ground. 



I have lately tried floating the cleaned material 

 to separate the blacks, but the foraminifera again 

 sank at once. 



4. Mud from Menai Straits. 



In several places along the Penrhyn foreshore and 

 elsewhere small patches strewn with white particles 

 were seen left by the receding tide. I scraped up 

 the mud containing these particles until there was 

 sufficient to fill two-thirds of a two-ounce tobacco 

 tin, and, after straining through a wire-gauze 

 coffee-pot strainer, rocked batches of the material 

 in water; then repeated the process with the 

 separated portion, finally rocking more slowly to 

 remove vegetable and other debris. The result 

 was a teaspoonful of a mixture of foraminifera and 

 blacks, with a small percentage of mica. The 

 proportion of blacks was considerable— say, one- 

 third to two-thirds of the total material — so that 

 mounting spread slides was out of the question, 

 and I determined to have another attempt at float- 

 ing. Before doing so the material was dried and 

 sifted with the finest sieve I had, the foraminifera 

 practically all passing through. On introducing 

 into water through a paper funnel, pouring a little 

 water clown the funnel to clear the last foraminifera 

 away, and stirring the material, floating forms 

 immediately rose to the surface and mostly col- 

 lected round the edges of the glass. By lifting 

 out some of the surface floats with a little water in 

 a teaspoon, so as to lower the water in the glass, 

 the floats were chiefly left adhering to the sides, so 

 •could be collected with a brush and transferred to 

 water in the teaspoon, poured into a filter and 

 dried. The floats only amounted to a small pinch 

 of material, but they were almost pure foramini- 

 fera, including a sparse sprinkling f flask shells or 

 Lagenidae ; these last are of several species, hardly 

 two on any slide being alike. 



On drying and refloating the sediment I ob- 

 tained a very little more foraminiferous material, 

 but the majority of the foraminifera which would 

 float had evidently come off in the first operation. 

 The sediment contained some forms that would not 

 float, and with the small quantity of material 

 ■operated upon it was impossible in any way to 



separate these foraminifera from the blacky espe- 

 cially as the 'blacks now largely preponderated 

 over the foraminifera. This material having yielded 

 successful surface floats, 1 tried to dispense with 

 some of, the preliminary washings ; but the floats 

 were neither so abundant nor so free from foreign 

 matter. In one case the floats had to be dried and 

 refloated to give satisfactory results. 



5. Black-rock. Brighton. 



Wishing to show some foraminifera to a friend 

 at Brighton, I gathered somewhat hastily some 

 sand from the rock-pools in that locality. This 

 sand apparently consisted of patches of coarse 

 material containing large Miliolinae, and other 

 patches of finer sand containing smaller shells, the 

 two kinds being mixed in collecting. The gather- 

 ing was rather roughly cleaned in a soup-plate ; 

 but on returning home and floating the small 

 quantity obtained, both the large Miliolinae and 

 the smaller forms floated. By sifting through the 

 finest gauze the large Miliolinae were obtained in 

 a state of purity, and the smaller forms which 

 passed through the sieve were sufficient to yield 

 one interesting slide, in which, however, they were 

 mixed with much foreign matter, especially blacks. 

 To separate these it would have been necessary to 

 operate on a larger quantity of material than I had 

 gathered. 



Thus, out of five kinds of material, the forami- 

 nifera in two floated, after the bulk of the sand 

 had been washed away ; those in the remaining 

 three refused to float. The experiments fully con- 

 firmed Mr. Earland's remarks as to the trouble of 

 dealing with " blacks." I tried burning out these, 

 by letting the material fall through a gas flame, 

 but the results were unsuccessful. The blacks are 

 evidently separable from the surface floats, and the 

 only possibility I can suggest of eliminating them 

 from foraminifera which sink at once is that the 

 foreign bodies light enough to be washed forward 

 with the foraminifera when the latter are full of 

 air may perhaps be carried in front of them when 

 the water has filled their chambers. Such a solu- 

 tion of the difficulty is probably easier in theory 

 than in practice. 



Foraminifera seem to me to be more dilVicuii to 

 clean than desmids, because when the material has 

 been separated into two or more portions by any 

 process of washing, it is necessary to use a hand 

 lens to see which portions contain the foraminifera, 

 whereas the bright green colour of the desmids 

 sufficiently indicates when these have been sepa- 

 rated from the foreign matter associated with them. 

 Plas Gwyn, Bangor, North. Wales. 



The Isaac Newton Studentship for en- 

 couraging research in astronomy and physical 

 optics, of the value of £200 per annum for three 

 years, has been bestowed, by election, on Mr. S. 

 Bruce M'Laren, B.A., of Trinity College, Cam- 

 bridge. 



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