19171 AGRICULTURAL BOTAXY. 29 



tested the relations between changes in respiration as noted in embryos of 

 Phaseolus vulgaris, etiolated stems of Vieia faba, and young leaves of Secale 

 cereale as related to different temperatures and to changes of temperature, 

 either gradual or more or less abrupt, and to restoration of former tempera- 

 tures. 



It is stated that sudden variations of temperature do not of themselves con- 

 stitute an excitant as regards respiration in plants. Between the respiratory 

 activity corresponding to a given temperature and that corresponding to a 

 different temperature the transition is gradual, and the course of respiration 

 change corresponds to that of temperature. 



The decrease of permeability produced by anesthetics, W. J. V. Ostebhout 

 {Bot. Gaz., 61 (,1916), No. 2, pp. 14S-158, figs. 6).— The present paper gives de- 

 tails, with discu.ssion, of some experiments previously reporlc 1 (E. S. R., 28, 

 p. 732) and of later researches on tissues of Lamiyiaria saccharina, as regards 

 their electrical conductivity under the influence of photosynthesis. 



It is stated that increase of permeability (except in case of alcohol within 

 certain limits) corresponds to a permanent injury and is not reversible. It 

 is not, therefore, to be regarded as a characteristic effect of the anesthetic. 

 The characteristic effect of anesthetics is regarded as being connected in some 

 way with decrease of permeability. It is stated that a decrease of permeability 

 may result in the decrease of irritability, which is the characteristic effect of 

 an anesthetic. 



Swelling and germination of seeds, J. Tkaube and T. Mabusawa {Internat. 

 Ztschr. Fhys. Chem. Biol., 2 {1915), No. 4-5, pp. 370-393).— It is stated that the 

 behavior of starchy seeds in relation to electrolytes and nonelectrolytes as 

 described corresponds essentially to that of starch. 



Swelling and differences therein are more considerable in case of such ni- 

 trogenous legumes as peas than in such cereals as barley. Narcotics retard 

 swelling, presumably on account of their flocculating effect on nitrogenous ma- 

 terial. The fact that acids and also indifferent narcotics retard swelling of 

 plant seeds is thought to indicate that swelling does not play the principal part 

 in germination. Indifferent narcotics cause more commonly a genuine narcosis, 

 but in some cases they cause irreversible injury. Acids still more often give 

 the latter result, the law of mass action possibly applying here to colloidal 

 phenomena. Some fatty acids appear particularly injurious. In certain low 

 concentrations citric acid greatly hastens germination of seeds. No constant 

 relation was noted between injury to germination and growth. 



The infl.uence of oxygenated water on germination, E. Demoussy {Compt. 

 Rend. Acad. Sci. [Paris], 162 (1916), No. 12, pp. ^^5-.}3S).— Reporting a study 

 of the kind of influence exerted by oxygen in favoring the germination of aged 

 seeds, the author states that 7-year-old seeds of garden cress which failed to 

 germinate when partly immersed in distilled water gave germination rates of 

 from 30 to 40 per cent in water containing oxygen, the time required for 

 germination being from three to ten days. The oxygen is thought to have re- 

 tarded the development of micro-organisms which find partial or total protec- 

 tion from antiseptics in mucilagenous layers of the seeds. The oxygenated water 

 was ineffective at low temperatures. Seed which failed to germinate in pure 

 water at 27° C. gave a germination rate of 25 per cent in moist sand at that 

 temperature, a result attributed to the increased access of oxygen. 



Studies on water transfer in plants, L. Jost {Ztschr. Bat., 8 {1916), No. 1, 

 pp. 1-55, figs. 12). — It is stated that the cut stump of a plant gives up much 

 less water than Is taken up at first by the portion which has been cut away 

 when this is placed in water, or than the intact leaf requires. The cause of this 

 alteration is thought to lie in the interruption of the connections in the tracheal 



