December i6, 1920J 



NATURE 



523 



liver, also infestation of Physopsis africana by water 

 containing the miracidia of Schistosoma haema- 

 tobium ; here the mature cercariae were found six 

 weeks later.— R. D. Aitkcn : The water relations of 

 the pine {Pinus pinaster) and silver-tree (Leucadendron 

 argetiteum). The conductivity of the wood for water, 

 rate of transpiration, total area of leaf-surface, and 

 sectional area of wood have been determined for 

 similar twigs of pine and silver-tree. Under the 

 experimental conditions pine leaves e.xerted a much 

 greater suction force, calculated in one instance to 

 be about four times that exerted by the silver-tree 

 loaves. The latter are less able to resist drying than 

 pine leaves, in which the rate of transpiration verv 

 rapidiv diminishes when the twig is not supplied with 

 water to a much lower level than in a silver-tree twig 

 under identical conditions.— J. W. C. Ounn : The 

 action of Eticomis undulata. E. undulata contains a 

 large amount of a sanoglucoside. soluble in water and 

 go per cent, of spirit. It is a powerful haemolvtic 

 agent. .Absorption of the extract from the stomach 

 and intestines and from the subcutaneous tissues is 

 ven- slow ; intravenous injections are actively 

 poisonous, and nroduce svmptoms like other saponin 

 bodies.— T. J. Mackic : A study of the Bacillus coli 

 group, with special reference to the serological 

 characters of these organisms. The paper is a de- 

 tailed record of investigations on the B. coli group 

 with reference to their (i) biological classification. 

 (2) serological characters, and (-i) mutations. The 

 biological characters of 246 strains of trram-nega- 

 tive, aerobic, non-sporing, and non-liquefving glucose- 

 fermetiting bacilli (not including soeclfic pathogens 

 of this class) were studied. Four main sub- 

 groups could be recognised : (a) Gas-producing, 

 indol-forming. and non-inosite-fermenting. (b) Gas- 

 producing, non-indol-forming, and non-inosite-fer- 

 menting. (c) Gas-producing and inosite-fermenting. 

 W) Nnn-gas.producing fanaerogenes tvpes). The sero- 

 logical characters studied were fi) the agglutination 

 and (2) complement deviation reactions of immune 

 sera to certain of the commoner varieties. These ob- 

 ser\ations proved of great interest from the purely 

 immunological point of view, and also threw some 

 further light on the biological relationships of the 

 various types of coliform bacilli. The comparative 

 r»"iist.'mce^ of various tvpes to brilliant green was cor- 

 ' ited with the groupinf determined bv cultural and 

 >lof<ical tests. Mutations among these org.nnisms 

 re investigated, and afforded some explanation of 

 great diversity of cultural types and of the high 

 roe of specialisation in the serological characters 

 individual strains. — E. Newbery : Note on over- 

 vollapes. Over-vollage appears to be a function in- 

 de[>endent both of the ens liberated and of the metal 

 in question, and completely determined bv valency 

 alone. Whether the valency of the gas is involved or 

 not is still an open question, since all gaseous ions 

 usefl were monovalent. The over-voltage comoounds 

 probably carry excess electrons, and the addition of 

 each electron nrodiires a definite increment in the 

 sint'le potential, which increment is dependent onlv 

 upon the number of free valency electrons present in 

 the atom of the clertrmle nr ion of the ovrr-voltage 

 compound. 



Books Received. 



Manual of Tropical ami .Siititropiral Fruits : Ex- 



ling the Banana. Coconut. Pineapple, Citrus 



its, Olive, and Fig. Bv W. Popeno*-. (Rural 



.M.inunls.) Pp. xv + 474 + xxiv plates. (New York: 



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NO. 2668. vol.. 106] 



The Principles of Preventive Medicine. By Prof. 

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Root Development in the Grassland Formation : A 

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The New Physics. By Dr. A. C. Crehore. Pp. 

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Phvsics of the Air. By Prof. W. J. Humphreys. 

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The Physico-Chemical Properties of Steel. By 

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The Platinum Metals. By A. D. Lumb. (Imperial 

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Das Naturbild dcr Neuen Physik. By Prof. A. 

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The Northern D'Entrecasteaux. By D. Jenness and 

 the late Rev. A. Ballantyne. Pp. 219. (Oxford: 

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The Progress to Geography. Edited by Dr. R. 

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Recent .Advances in Organic Chemistry. By Prof. 



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! Department of the Interior. L'nited States Geo- 



] logical Survey. Bulletin S97 = Geology of Massa- 



I chusetts and Rhode Island. Bv B. K. Emerson. 



' Pp. 289+x plates. Professional Paper 96: The Geo- 



' logy and Ore Deposits of Ely, Nevada. By Arthur C. 



I Spencer. Pp. 189+xv plates. Professional Paper 99 : 



; Chemical Analyses of Igneous Rocks. Published from 



' 1884 to 1913' inclusive. Bv 11. S. Washington. 



Pp. 1 201. Professional Paper iii : The Ore Deposits 



of Utah. By B. S. Butler and others. Pp. 672 + 



Ivii plates. (Washington : Government Printing 



Office.) , rv . 



La Chimie et la Vie. By G. Bohn and Dr. .\. 



Drzewina. Pp. 275. (Paris: E. Flammarion.) 



7.50 francs. 



Laboratory Manual of the Technic of Basal Meta- 

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.Advanced Lessons in Practical Physiology for 

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.A Course of Practical Physiology for Agricultural 

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Girolamo Sarrheri's Euclides Vindicatus. Edited 

 and translated bv Dr. G. B. Halsted. Pp. xxx + 246. 

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 Co.) los. net. 



The Early Mathematical Manuscripts of I.eil>ni?,. 

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 Imnianuel Gerhnrdt, with critical and historical notes 

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 net. 



The Reversal of Halphen's Transformation. By 

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 Dead Man's Plack and an Old Thorn. lU \\ . II. 



