ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 1019 



by ether in certain doses. In anesthetized tissues the chlorophyll- 

 bodies do not take up their nocturnal position, but remain wherever 

 they happen to be at the moment of anesthesis. 



Chemistry of the ripening of Seeds.* — M. A. Miintz has ex- 

 amined the structure of starchy and oily seeds at different periods of 

 ripening. 



As an example of starchy seeds he took in the first place rye. It 

 was found to contain at all periods of ripening a carbohydrate with 

 no rotatory power, and without action on the copper reagent, but 

 which is transformed as readily as cane-sugar into a levogyrose 

 glucose which reduces Fehling's solution. These properties corre- 

 spond to those of synanthrose or levuline, hitherto known only in the 

 roots of Composita3. As the grain ripens, this synanthrose is gradually 

 converted into starch, apparently directly, without going through any 

 intermediate stages. 



In grains of wheat as large a quantity of synanthrcse was found as 

 in rye ; the same substance was found also in grains of barley and 

 oat, but not in maize. The grains of the true cereals contain also, in 

 addition to the synanthrose, a strongly inverting ferment ; in the 

 cases of wheat, oat, and barley, the synanthrose has been entirely 

 converted into starch in the ripe seed. The synanthrose was found 

 also in the stem and leaves. 



For oily seeds, colza was taken as an example, the carbohydrates 

 were found to he starch, a gum soluble in w r ater and precipitated by 

 alcohol, cane-sugar, and inverting sugar. The oil is formed very 

 rapidly during ripening, at the expense of the starch and glucose ; but 

 in the very last period it again suffers some diminution, apparently 

 the result of respiration, since the total weight of the seed is also 

 somewhat reduced. 



What is Diastase ? | — Herr J. Fankhauser has investigated the 

 chemical processes which go on in germinating potatoes and harley, 

 and finds that the conversion of starch into sugar is not effected by 

 microbes, but by a substance of a perfectly definite composition, 

 identical with formic acid. In a control experiment he demonstrated 

 that formic acid possesses the property of converting starch into sugar. 



Action of Diastase and Invertin. X — Herr H. Miiller-Thurgau 

 alludes to several points in the influence of these substances on the 

 vital processes of plants. Their action in relation to temperature 

 differs from most physiological processes in being not inconsiderable 

 even at 0° C. The relative activity of diastase at the temperatures 0°, 

 10°, 20°, 30°, and 40° is represented by the numbers 7, 20, 38, 60, 

 98 ; that of invertin by 9, 19, 36, 63, 93. Diastase acts on starch in 

 the living cells also under a high pressure, amounting to several atmo- 

 spheres, when the cell-sap is probably saturated with C0 2 . Even at 

 ordinary temperatures, CO., has the property of increasing nearly 



* Ann. Sci. Nat. (Bot), iii. (1886) pp. 45-74. 



t Der Bund, xxxvii. (1886). See Bot. Centialbl., xxvi. (1886) p. 323. 

 J Landwirtbscb. Jabrb., 1885, pp. 795-822. See Bot. Centralbl., xxvii. 

 (1886) p. 143. 



