Apeil 3, 1896.] 



SCIENCE. 



529 



3. In sulphur chloride the sulphur is appar- 

 ently dissociated to the same extent as in the 

 vapor at high temperatures, the molecular 

 complexity being represented by Sj. 



On the Determination of Sulphur in Illuminating 



Gas and in Coal. By Chaeles F. Mabeey. 



The author uses a modification of Bauer's 

 method, burning the gas in a tube in a stream 

 of air, the products formed being absorbed in a 

 standard alkaline solution. The coal is burned 

 in the same way, being introduced into the 

 tube in a platinum boat. The amount of sul- 

 phur left in the ash is less than 0.05 per cent, 

 on an average. 

 Chemistry of the Berea Grit Petroleum. By 



Chaeles F. Mabeey and O. C. Dunn. 



A brief account is given of the most impor- 

 tant wells and their output, and the character 

 and properties of the petroleum from the Berea 

 Grit. 

 A Method for the Standardization of Potassiura 



Permanganate and Sulphuric acid. By H. N. 



MoESE and A. D. Chambees. 



If a known quantity of standard sulphuric 

 acid is treated with hydrogen peroxide and 

 potassium permanganate added as long as the 

 color disappears, and more hydrogen peroxide 

 and permanganate added until most of the acid 

 has been used up, and the excess determined 

 by titration with the standard ammonia solu- 

 tion, the strength of the permanganate can be 

 easily calculated. 

 Some derivatives of unsymmetrical Tribromhenzol. 



By C. LoEiNG Jackson and F. B. Gallivan. 



The authors find that two of the bromine 

 atoms in tribromdinitrobenzol are easily re- 

 placed by treating with aniline or sodic ethy- 

 late. A number of derivatives are described. 



Besides a review of recent work on Helium, 

 and notes on the composition of Barium Picrate, 

 and the proposed changes in the BericMe and 

 ' Beilstein,' this number contains reviews of the 

 following books : 



' Kurzes Handbuch der Kohlenhydrate,' Dr. 

 B. Tollens; 'Die Chemie der Zuckerarten,' Dr. 

 E. O. von Lippmann; ' Ostwald's Klassiker, Zur 

 Entdeckung des Elektromagnetismus,' and 

 ' Die Anfange des natiirlichen Systemes der 

 chemischen Elemente ;' ' Die Lehre von der 



Elektrizitat,' G. Wiedemann; ' Physikalisch- 

 chemische Propsedeutik,' H. Griesbach ; 'A 

 Laboratory Manual of Organic Chemistry, ' Dr. 

 Lassar-Cohn ; ' Jahrbuch der Elektrochemie; ' 

 ' Anleitung zur Molekular-gewichtsbestimmung 

 nach der Beckmannschen Gefrier- und Siede- 

 punkts-Methode, ' Dr. G. Fuchs ; ' Einfiihrung 

 in die mathematische Behandlung der Natur- 

 wissenschaften, ' W. Nernst ; ' Elements of 

 Modern Chemistry,' C. A. Wurtz. 



J. Elliott Gilpin. 



PSYCHE, APRIL. 



S. H. ScuDDEE gives a table to separate the 

 13 New England species of Melanopli, 10 of 

 them belonging to the genus Melanoplus; H. F. 

 Wickham continues former studies on myrme- 

 cophilous Coleoptera ; and a notice is added 

 of Plateau's recent experiments on insect vision. 

 A Supplement contains the conclusion of C. F. 

 Baker's account of some new New Mexican 

 Homoptera and the beginning of descriptions of 

 new species of bees of the genus Prosopis (or 

 Prosapis, as the author prefers), by T. D. A. 

 Cockerell. 



SOCIETIES AND ACADEMIES. 



NEW YOEK ACADEMY OP SCIENCES. 



At the meeting of the Biological Section, on 

 March 9th, 1896, Mr. F. B. Sumner read a 

 paper on ' The Descent Tree of the Variations 

 of a Land Snail from the Philippines,' illus- 

 trated by a lantern slide. Mr. Sumner described 

 the range in variation in size and markings in 

 the shell, and arranged the varieties in the form 

 of a tree of three branches diverging from the 

 most genealized tj'pe. It was shown that these 

 several varieties occupy the same geographical 

 region, and Mr. Sumner was of the opinion that 

 their occurrence could not be explained by 

 natural selection since if the colorations were 

 supposed to be protective it would be impossible 

 to explain the evolution of these three types. 

 Prof. Osborn, in discussion, was inclined to 

 take the same view. Dr. Dyar, however, 

 thought the explanation by natural selection 

 not necessarily excluded, since the variations 

 seemed analogous to the dimorphism in sphinx 

 larvae, which has been shown by Poulton to be 

 probably due to this factor. 



