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SCIENCE-GOSSIP. 



CONDUCTED BY J. H. COOKE, F.L.S., F.G.S. 



To whom Notes, Articles and material relating to Microscopy, 



and intended for Science-Gossip, are, in the first instance, to 



be sent, addressed "/. H Cooke, Thomdale, Lincoln." 



Microscopical Studies. — Those of our readers 

 who are in search of material for study during the 

 forthcoming winter months, should write for the 

 very detailed catalogue which has just been 

 issued by A. Flatters, 16, Church Road, Longsight, 

 Manchester. We have also received details from 

 S. P. Bolton, 25, Balsall Heath Road, Birmingham, 

 of the tubes of zoological and botanical objects that 

 he issues weekly with notes and drawings. 



Protozoa of Salt Lakes. — Dr. P. Butschinsky, 

 says the "Journal of Microscopy," has studied the 

 Protozoa found in two salt lakes or limans, near 

 Odessa. They are more abundant in the lake with 

 less salinity, and they consist partly of freshwater 

 and partly of marine species. The fauna of the 

 two lakes is not the same, and in both cases very 

 striking fluctuations occur. 



Life Cycle of Coccidia. — In the " Comptes 

 Rendus," M. Louis Leger gives the results of his 

 researches on the life-history of various Coccidian 

 parasites in Myriopods and Insects. He expresses 

 the opinion that in Arthropods, the genus Eimeria 

 does not represent a distinct parasite, but rather a 

 stage in the life-cycle of a Coccidian. There seems 

 to be no case known in which an Arthropod with 

 Coccidia does not also include phases of an 

 " Eimerian " cycle. 



Acetylene Gas in Photomicrography. — Acety- 

 lene gas as an illuminant in photomicrography, has 

 been recommended by several workers during the 

 past year. It is specially adapted to this work on 

 account of its brilliancy and steadiness, and also 

 for its portability, cheapness and safety in use. 

 Mr. W. H. Walmsley renders the light mono- 

 chromatic by means of a cobalt blue cell placed 

 in the substage of the microscope, while Mr. T. J. 

 Bray points out that many details otherwise un- 

 obtainable may be brought out by using a bichro- 

 mate cell. 



A Simple Condenser. — A simple, inexpensive, 

 and most effective condenser for use with high 

 powers may be made by mounting one of the 

 glass spheres which takes the place of a cork in 

 lemonade bottles. We have had one in use for 

 some time, and have found it most useful and 

 efficient as an auxiliary to, or in place of, an 

 Abbe condenser. 



Taxonomic Value of Scales of Lepidoptera. 

 — Mr. V. L. Kellogg discusses in the 'pages of the 

 " Kansas University Quarterly," the structure and 

 office of the scales of Lepidoptera, and concludes 

 that the most generalized scale is the small hair 

 without specialized insertion ; while the most 

 specialized scale is the broadened toothed form 

 with a pedicel and a cup-shaped insertion on 



the surface of the wing. He applies the principle 

 laid down by Comstock in his consideration of 

 venation and shape of wing, and finds that his 

 results coincide practically with the taxonomic 

 conclusions reached by Professor Comstock. 



British Mycology During Sixty Years. — 

 In the course of an address by Dr. M. C. Cooke 

 before the Essex Field Club on the progress made 

 in the study of British Mycology, attention was 

 drawn to the vast strides that have of late years 

 been made in this study in consequence of the 

 increased attention that has been given to the 

 subject by microscopists. In the year 1836 about 

 1,390 fungi were catalogued, but in 1896 acquaint- 

 ance had been made with no less than 40,000. He 

 alluded, too, to the discoveries of the brothers 

 Tulasne concerning polymorphism, the work of 

 Du Bary on fermentation, and Pringsheim's 

 labours on the subject of symbiosis. These 

 specialists, by confining their attentions each to 

 one branch, have separated many hitherto mixed 

 species of fungi by the exactness of their 

 observations. 



Microscopic Bubbles in a Sapphire. — Movable 

 bubbles are often seen in quartz and other 

 crystals, but the appearance and disappearance 

 of inclusions of this kind is a bit of nature's magic 

 not often observed. An interesting experience 

 with a cerulean blue sapphire is described by 

 Mr. W. S. Beekman in " The Microscope." This 

 was a beautiful gem of nine carats, but it had a 

 flaw, and one cold morning he was astonished to 

 see a moving bubble in this flaw as he picked up 

 the stone. He hastened away to show the phe- 

 nomenon to a friend. He could find no bubble 

 for his friend, however, and at home he sought it 

 again in vain, then tried to reason that it had in 

 some way worked out of the stone. The search 

 was resumed in the evening. Turning on the 

 light, there again was the bubble, but it was 

 falling to pieces, and in a few moments had dis- 

 appeared. Its vanishing was a trick of tempera- 

 ture. Between 85° and 86° Fah. — which is the 

 critical point of carbonic acid when under a. 

 pressure of 90 atmosphere — the bubble changed 

 from a liquid to an invisible gas. 



Dissemination of Disease Germs. — A bacteri- 

 ological examination of two New Testaments that 

 have during the last sixty years been kissed by 

 about 40,000 persons in the West Riding of York- 

 shire, revealed seven species of micro-organisms. 

 None of the germs were harmful, though they 

 included various cocci, bacilli, moulds, yeasts and 

 schizomycetes. Mr. F. W. Richardson, consulting 

 chemist to the Bradford Corporation, has pub- 

 lished an interesting report on the results of the 

 examination 



Photomicrography of Opaque Stem Sections. 

 — Mr. R. A. Robertson, M.A., B.Sc, gave a de- 

 monstration before the Botanical Society of 

 Edinburgh, illustrating the methods he adopts in 

 making photo-micrographs of recent and fossil 

 stem sections. He has found that he can obtain 

 all necessary histological details by directly 

 photographing the surface with a micro-photo- 

 graphic apparatus. He planes down the surface 

 of the wood with a steel plane. The only difficulty 

 is the focussing, and this should be done first on 

 a semi-opaque focussing plate, and finally on a. 

 focussing plate of clear glass. The illumination 

 was by means of a magnesium ribbon fed through 



