122 PHYSIOLOGY [Bot. Absts., Vol. V, 



optically active alkaloid or acid, centuries after the plant that produced it is destroyed, will 

 still retain its activity, and the occurrence of any optically active substance, such as petro- 

 leum, proves that it must have been derived from living tissues. — Experiments with hyos- 

 cyamine, a laevorotatory substance and its isomer atropine, optically inactive, consisting 

 of equal parts of laevo and dextro hyoscyamine, demonstrated that Z-hyoscyamine had the 

 same physiological effect on peripheral nerve-endings as twice the quantity of dZ-hyoscyamine 

 (atropine) . Again, a comparison, by the effect on blood pressure, indicates that natural adren- 

 aline (Z-adrenaline) was twice as powerful as synthetic adrenaline (dZ-adrenaline) and that 

 d-adrenaline (obtained from dZ-adrenaline) was without activity. — E. N. Gathercoal. 



880. Haas, A. R. C. The electrometric titration of plant juices. Soil Sci. 7: 487-491. 

 1 fig. 1919. — An electrometric apparatus is described for determining the buffer action, 

 acid and alkali reserve, and the total and actual acidities of plant juices. Rhubarb juice has 

 a greater actual acidity and greater buffer action than that of soy bean tops. — William J. 

 Robbins. 



881. Haynes, Dorothy, and Hilda Mary Judd. The effect of methods of extraction 

 on the composition of expressed apple juice, and a determination of the sampling error of such 

 juices. Biochem. Jour. 13 : 272-277. 1919.— See Bot. Absts. 5, Entry 541. 



882. Jones, Harry. Some factors influencing the final hydrogen-ion concentration in 

 bacterial cultures with special references to streptococci. Jour. Infect. Diseases 26: 160-164. 

 1920. — The composition of the medium, the initial reaction and any other conditions which 

 favor or hinder abundant growth of a given organism should be considered in order to obtain 

 accurate information regarding its final hydrogen ion concentration. — Sclman A. Waksman. 



883. Knudson, L., and E. W. Lindstrom. Influence of sugars on the growth of albino 

 plants. Amer. Jour. Bot. 6: 401-405. 1919.— Albino corn seedlings grown both on agar and 

 in water culture were supplied with sugar (sucrose and glucose). On agar, they all lost weight, 

 but those supplied with sugar lost considerably less than controls which had no sugar. Re- 

 sults with plants grown in the dark were essentially the same as with those grown in the light. 

 In water culture the albino seedlings made an appreciable gain when provided with sugar, 

 and lived much longer than the controls, but ultimately died. The better growth in water 

 culture is explained as probably due to higher concentration of sugar and higher temperatures 

 at which the plants were grown. Roots of plants supplied with sugar often continued to 

 live for some time after the shoots died. The substitution of asparagin for nitrates in the 

 culture solutions caused practically no difference in growth. The authors explain the failure 

 of albino plants to thrive when sugar is supplied as due to the inability of the plant to absorb 

 sugar rapidly, and to the relatively slow rate of its conduction. — E. W. Sinnott. 



884. Kremers, R. E., and J. A. Hall. On the identification of citric acid in the tomato. 

 Jour. Biol. Chem. 41 : 15-17. 1920. — The presence of citric acid in the tomato has been shown 

 by means of its triphenacyl ester. — G. B. Rigg. 



885. Meinicke, E. Die Lipoidbindungsreaktion. [The lipoid-fixation reaction.] Zeit- 

 schr. Immunitatsforsch. u. Exp. Therapie 27: 350-363. 1918; 28: 2S0-326. 1919.— Antibodies 

 are probably globulins, or at least inseparable from them by any known method. In the reac- 

 tion between serum and the extract, the colloids of the latter force the NaCl equivalent of 

 the serum globulins from solution, probably by removing NaCl. This reaction is stronger 

 in positive sera. An immunized organism reacts more quickly and more intensively follow- 

 ing a recent addition of antigen than the control. The possibility of a specific, more intensive 

 reaction resides not only in the cell but also in the serum itself. The intensity of the reaction 

 seems due to the fact that the NaCl equivalent of the most labile substance in the system is 

 forced out of solution by the most stable substance present. The various forms of immunity 

 reactions are only the expression of the different reagents acting in various combinations in 

 such a system, hence it is possible to combine various forms of reactions. In the so-called 



