400 SUMMARY OF CURRENT RESEARCHES RELATING TO 



found that the distinctive diagonal double rows of " pearls " have the 

 primaries crowned with a very beautiful kind of perforated secondary 

 structure which should be within the reach of any good oil-immersion 

 lens capable of standing a large working aperture. The author has 

 also found that N. Crabro, a form analogous although differently 

 shaped to N. Smithii, and possessing likewise a double row of " pearls," 

 also possesses an exactly similar structure. The specimens, presumably 

 Belgian, figured in "Van Heurck (Plate B, fig. 23, and plate ix., fig. 1), 

 do not show these secondaries. It may be that there is a difference in 

 structure between the Belgian and Italian varieties of these diatoms. 



Quekett Microscopical Club. — The 45Gth Ordinary Meeting was 

 held on April 2, Mr. C. F. Rousselet, F.R.M.S., Vice-President, in 

 the Chair. Mr. C. Lees Curties, F.R.M.S., for Messrs. Baker, gave an 

 interesting exhibition of some of the different illuminants for the 

 Microscope. A paper by E. Heron-Allen, F.L.S., F.R.M.S., and 

 A. Earland on " A new species of Technitella from the North Sea, with 

 some observations upon Selective Power as exercised by certain species 

 of Arenaceous Foraminifera " was read by Mr. Earland. The new 

 species is Technitella Thompson i sp. n., and is fully described and 

 illustrated in the current Journal of the Quekett Microscopical Club 

 (April 1D0D). The test is built up entirely of echinoderm plates. 

 Mr. E. F. Law gave a lecture, illustrated with photomicrographs in the 

 lantern, on " The Relation between the Microscopic Structure and 

 Properties of Alloys." 



At the 457th Ordinary Meeting held on May 7 the postponed 

 presidential address was delivered by Professor E. A. Minchin, M.A., 

 F.Z.S., who took for his subject " Some Applications of Microscopy 

 to Modern Science and Practical Knowledge." He gave a very 

 interesting account of malaria, sleeping sickness, and yellow fever, 

 describing the life-history, so far as it is at present known, of the 

 parasites causing these respective diseases. 



B. Technique.* 

 (1) Collecting- Objects, including- Culture Processes. 



Flask for Fluid Media.-f— A. H. Caulfield advises the following 

 modification of the flasks used for holding fluid media by which the 

 wetting of the plug from often unavoidable shaking is obviated. The 

 neck of an ordinary flask is throttled and plugged by a glass ball rather 

 larger than the contriction : this can be readily blown from a piece of 

 small glass tubing, and if provided with a short handle it can be 

 conveniently held in position by the wool plug. The author found this 

 form of flask useful for cultures made on patients living at a distance 

 from the laboratory. 



* This subdivision contains (1) Collecting Objects, including Culture Pro- 

 cesses ; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes ; 

 4) Staining and Injecting ; (5) Mounting, including slides, preservative fluids, etc. ; 

 (6) Miscellaneous. 



t Centralbl.Bakt., lte Abt. Orig., xlix. (1909) p. 463. 



