6 4 



SCIENCE-GOSSIP. 



call a '• vital force." A plasmodium like Aethalium 

 septicwm (flowers of tan) is susceptible to the 

 slightest possible change in surrounding conditions. 

 When exposed to light of any great intensity, such 

 as the electric arc, it will, if observed, be seen to 

 move towards a spot where the light is of least 

 intensity, and if any shadow exists will be found 

 in that shadow if near enough. If kept for some 

 time in a dry spot, and then exposed to the influence 

 of moisture — say a piece of damp blotting-paper 

 placed in the vessel in which they are kept — the 

 Plasmodia will move towards this moist area, and 

 soon be found to aggregate where most moisture 

 is present. It has been stated that gravity has not 

 any effect upon plasmodia ; that is, they are said 

 to be " non-geoptric." It may be that the surface- 

 tension exerted by a plasmodium situated upon, 

 say, a vertical glass plate is quite sufficient to 

 overcome the force of gravity, or perhaps that 

 gravity has no effect at all upon such a plasmodium. 

 Chemotropism is well marked in Aethalium; dilute 

 solutions of tan or of infusions of decaying matter, 

 such as that existing in humus, are found to exert 

 a direct attraction for the plasmodia ; whereas a 

 solution of sodium chloride will have a repellent 

 action. In the former case the plasmodium is posi- 

 tively chemotropic, in the latter negatively so. Now 

 it is quite impossible to say whether or no there be a 

 " vital force " underlying all these phenomena ; 

 one would be rather inclined to the belief that this 

 so-called "vitality" is nothing more nor less than 

 the combined effect or the relative action of these 

 various forces — light, heat, chemical, etc. — upon 

 the delicate molecular constitution of the proto- 

 plasm, and not a specific form of energy apart from 

 the others. 



NOTICES OF SOCIETIES. 



Ordinary meetings are marked f, excursions* ; names of persons 

 following excursions are of Conductors. Lantern Illustra- 

 tions^. 



South London Entomological and Natural History 

 Society. 



July 6. — * Brasted, Kent.". E. Adkin. 



Birkbeck Natural History' Society. 



July 13. — * Oxted for Limpsfield Common. 0. H. Williams. 

 „ 20. — * Broxbourne. Miss A. R. Rollinson. 



Geologists' Association. 



July 6.—* Twyfortf. LI. Treacha-, F.G.S. 



., 13.—* Woolwich. W. Whitaker, B.A., F.R.S. 

 „ 20.— * Pulborough. J. V. Elsden, F.G.S. 



Hampstead Scientific Society. 



July 19. — * Zoological Society's Gardens, Regent's Park. 



Yorkshire Naturalists' Union. 

 July 15.—* Wetherhy. 



Nottingham Natural Science Rambling Club. 



July 13. — * Teuton — Geology. 

 „ 27. — » Burton Joyce — Botany. 



Acton Scientific Society and Field Club. 

 July 13. — * Wimbledon Common. 



„ 2ii.—* Mr. Read's Collection of Birds' Eggs at Bedford 

 Park. A. Ramsey. 



,, 20. — * Rothschild Museum and Park, Triug. 



ANSWERS TO CORRESPONDENTS. 



J. R. (Loughton). — You will find the information required in 

 Dr. Knagg's " Lepidopterist's Guide," one shilling, to be 

 obtained from Messrs. Watkins & Doncaster, 36 Strand, or 

 Messrs. Gurney & Jackson. 1 Paternoster Row. 



NOTICES TO CORRESPONDENTS. 



To Correspondents and Exchangers. — Science-Gossip is 

 published on the 25th of each month. All notes or short com- 

 munications should reach us not later than the 18th of the month 

 for insertion in the following number. No communications can 

 be inserted or noticed without full name and address of writer. 

 Notices of changes of address admitted free. 



Editorial Communications, articles, books for review, instru- 

 ments for notice, specimens for identification, etc., to be addressed 

 to John T. Carrington, 110 Strand, London, W.O. 



Business Communications. — All business communications 

 relating to Science-Gossip must be addressed to the Manager, 

 Science-Gossip, 110 Strand, London. 



Subscriptions. — The volumes of Science-Gossip begin with 

 the June numbers, but Subscriptions may commence with any 

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Notice. — Contributors are requested to strictly observe the 

 following rules. All contributions must be clearly written on 

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 names must be given in full, excepting where used immediately 

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The Editor will be pleased to answer questions and name 

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 Specimens, in good condition, of not more than three species to 

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 ticulars of capture. 



The Editor is not responsible for unused MSS., neither can he 

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EXCHANGES. 



Notice. — Exchanges extending to thirty words (including 

 name and address) admitted free ; but additional words must be 

 prepaid at the rate of threepence for every seven words or less. 



Wanted, a few fresh stems of Equisetum hyemale. Botanical 

 or insect slides offered in exchange. — Walter White, Litcham, 

 Swaffham. 



Offered, 90 species of Barton Fossils. Wanted, micro- 

 objects, mounted or unmounted, mounting material, celloidin, 

 slips, etc., or offers. — G. Granville Buckley, Norwood, Oldham. 



Offered, " The Midland Naturalist," 115 Nos., 1884-1893 ; 

 "American Microscopical Journal," 1896-1901; " Insect • Life," 

 copiously illustrated; "Annual of Microscopy," 1900; miscel- 

 laneous micro-literature. Wanted, good pair field glasses ; geo- 

 logical works. — T. H. Cooke, 1 Henleare, Bristol. 



AVanted, a few living plants of the true Oxlip, Primula 

 elatior ; from Cambridgeshire preferred. Primrose and Cowslip 

 Hybrid not wanted. Useful exchange given.— Joseph Meade, 

 36" Freeman Road, Birmingham. 



Wanted, some back numbers of " Journal of Botany " (first 

 series) to exchange for other numbers. — C. H. Waddeil, Saint- 

 field, Co. Down. 



CONTENTS. 



PAGE 



Radiograph of Naja Tripudians. By C. Ainswortk 



Mitchell, B.A. (Oxon.) Illustrated 33 



An Unrecognised Pioneer. By W. Johnson . . . . 34 



Food of Prehistoric Man. By T. Charters White . . 36 

 Classification of British Ticks. .By Edward G. 



AVheler. Illustrated 37 



Irish Plant Names. By John H. Barbour, M.B. . . 41 

 Butterflies of the Palaearctic Region. By Henry 



Charles Lang, M.D. Illustrated 43 



British Freshwater Mites. By C. F. George, M.R.C.S. 



Illustrated . . .. . . . . . . . . . . 44 



New Edition of " Staudinger'S Catalogue" .. ..47 



Books to Read, illustrated 48 



Science Gossip 50 



Photography, illustrated 51 



Chemistry . r > i 



Microscopy, illustrated 55 



Astronomy-. Illustrated 58 



Notes and Queries. Illustrated, 61 



BOTANY. Illustrated 62 



Notices — Exchanges 64 



