

1907] CURRENT LITERATURE 157 



The lowlands area is presented under the following formations: dune, muddy 



salt marshj rocky headlands, aquatic, and peat moor. The section given to a 



t . consideration of the upland area contains an account of the plant formations of 



the sandstones, the limestones, the deep marls and clays, and the region of culti- 

 vation. The history of the plant formations is traced, it being shown that a 

 plant formation begins as an open or unstable association, passes through inter- 

 mediate associations, and eventually becomes a closed or stable association. . For 

 example, the dune formation in this region begins as an open association, either 

 of strand plants, or of Agropyron jiincetim, or of Ammophila arundinacca, and 

 only reaches the intermediate associations of dune pasture plants or of dune marsh 

 plants. The formation of the muddy salt marshes begins as an open association 

 of Salicornia, and, after reaching an intermediate association of halophilous plants, 

 the salt marshes are reclaimed. The author concludes that in a small area, like 

 England, the plant associations are determined much more by edaphic factors 

 than by climatic conditions. — J. M. C. 



Toxicity of solutions, — To determine if the fact discovered by Nageu, that 

 insoluble solid substances placed in poisonous solutions in which algae are grow- 

 ing reduce the toxicity of the solutions, holds also for fungi, Miss Fitch'^ has 

 investigated the action of insoluble substances upon media in which fungi were 

 grown. Penicillium and Aspergillus were grown in pure cultures in beet decoction, 

 in prune decoction, and in bouillon to which sulfuric acid had been added, making 

 concentrations of w/4, m/8, «/i6, w/32, w/64, and n/i2S, It was found that such 

 substances as glass in different degrees of fineness, sand, and filter paper reduce the 

 degree of toxicity of the poisonous solutions. For example, in cultures of Aspergil- 

 lus in beet decoction, n/64 and w/128 H2SO4 showed stimulation, while w/32 was 

 near the border line of be^nning toxicity; but with the addition of glass n/^2 

 showed the greatest stimulation of growth of the series, and a concentration as high 

 as n/16 still showed marked stimulation. All other experiments showed results 

 of the same nature, thus establishing the fact that the principle of Nageli holds 

 in this case, as it has been shown to hold for flowering plants. Such results were 

 to be expected, since the modifying action of the solid substances is exerted on 

 the solution and not on the organisms growing therein. — H. Hassklhring. 



Glycogen and sporulation in yeast, — Kohl'* finds that glycogen is more 



abundant in actively budding cells of Saccharomyces cerevisiae which he examined 

 than it is in the resting cells. In view of this fact he believes that glycogen is net 

 exclusively a reserve product, but that it represents an ii 



the formation of alcohol from sugar. He suggests that glycogen is broken down 

 to glucose and isomaltose, which undergo splitting into alcohol and CO3 by the 

 action of zymase, and that the hexoses consequently first undergo transformadon 



* 5 Fitch, Rvby, The action of insoluble substances in modifying the effect of 

 deleterious agents upon the fungi. Ann. Mycol. 4:313-322. 1906. 



^^ Kohl, F. G., Ueber das Glykogen und einige Ersthcinungen bei der Sporula- 

 tion der Hefe. Ber. Deutsch. But. Gesells, 25:74-85. pi I- figs- 2. 1907. 



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