BOTANY. 743 



On the separation of laccase and tyrosinase found in certain mushrooms, 



(J. Bkktk.ojd (liiil. Mus. Hist. yaf. Pdris, 1S9G, So. 7, pp. SSS-SHO). 



"White wine vinegar, A. H. Allkx {Anahjnt, Jl {1S'J6), Oct., p. :?o4).— This vinegar 

 is uiado from the wine of the white grapo and may be distinguished from distilled 

 malt and diluted acetic acid vinegars from its containing considerable extractive 

 matter and acid potassium tartrate. — 15. av. kilgokk. 



The standardizing of permanganate of potash, V. E. Pavi^oI'' (Jour. Soc. Phys, 

 Chim. Jiimse, ;:'S, pp-C'l-SH; ahs. in Bui. Soc. Chim. Paris, 17-IS {1897), No. 2, pp. 

 S9-94). 



On some new forms of gas generators, T. H. NoitTox {Jour. Amer. Chan. Soc. 

 18 (1S96), Xo. 12, pp. 10o7-lu61, figs. 3). — Three new forms of generator are descril)ed, 

 one for hydrogen sulphid, etc., made of glazed earthenware and arranged so that 

 the acid may bo rendered of uniform strength; another designed for the same pur- 

 pose, which may be constructed in any Avell-equipped laboratory: and a third form, 

 an automatic cHlorin generator, ihe figures are necessary to explain the construc- 

 tion of each. — f. w. mdkse. 



Note on the durability of platinum-iridium vessels in laboratory use, T. Fair- 

 ley {Jour. Soc. (hem. Ind., 15 {1S96), No. 12, p. 55';).— The author exhibited vessels 

 made of alloy of platinum with 10 per cent of iridium, which had been in everyday 

 use more than 14 years. If carefully used the ware does not crack, as has been some- 

 times objected. — a. m. teter. 



The technique of physiological chemistry and pathology, A. Slos,se {Technique 

 de chimic physiolo<jiqiie et paOiologiqne. Brussels: M. Lannrtin, 1896, pp. -250, ill.), — 

 A laboratory manual. 



BOTANY. 



On the absorption and rejection of water by seed, H. Coupin 



[Ann. sci. nat. Bot., ser. 8, l* [1895), Xo. 1-3, pp. 12i)-;22;2, Jigs. 34). — An 

 extended study lias been made on the absorption of water by various 

 kinds of seed during* their swelling preliminary to germination and its 

 rejection during maturation. The work is divided into tliree parts, in 

 which were studied (1) the ordinary swelling of seed and their absorp- 

 tive power, (2) the increase in volume as comjiared with the amount of 

 water penetrating their integuments, and (3) the rejection of water 

 during maturation. In the lirst 2 categories only the physical phe- 

 nomena were studied, no attention being given the physiological and 

 chemical phenomena accompanying their swelling. 



The subjects for experimentation were seed of lupines, beans, peas, 

 wheat, maize, castor l)eans, hemp, barley, buckwheat, .sunflower, etc. 



The author gives a summary of his work, in which the following are 

 the most imi^ortant conclusions: 



Seeds are readily divided into 2 classes, dependent upon whether 

 their seed coats become wrinkled or not. 



When placed in water seeds do not swell equally in all dimensions, 

 and the i)ower of ab.sorbing water varies greatly for the same variety. In 

 some cases there is a (piantity of free water jtresent varying from one- 

 thirtieth to one-eighth of the total amount ab.sorbed. This amount is 

 greatest at the time of saturation and is considerably increased by the 

 use of an.esthetics. An increase of pressure increases the absorbing 

 power, while changes of temperature do not aftect it. An injiny to th© 



