AGRICULTURAL BOTANY. 429 



The toxicity of saccharin, E. Yerschaffelt (Pharm. WeekM., 52 (1915), Ko. 

 2, pp. 37-/,6; (lbs. in Jour. Chcm. Soc. [Londoii], 108 {1915), No. 629, I, p. 111).— 

 The studies here described, showing the toxic action of saccharin on plants, sug- 

 gest a general injurious influence on protoplasm, and hence on the human 

 organism. 



The effect of alkali on permeability, W. J. V. Ostekhout {Jour. Biol. CJiem., 

 19 {191Jf), No. 3, pp. 335-343, figs. 5). — Experiments by the author making deter- 

 minations on tbe electrical resistance of living tissues of Laminaria saccharina 

 are claimed to show that the permeability of the protoplasm (which is claimed 

 to be accurately measured by the method employed ) is considerably increased by 

 the pi'esence of a small proportion of sodium hydrate. 



The effect of acid on permeability, W. J. V. Osterhout {Jour. Biol. Chem., 

 19 (1914), No. 4, pp. 493-501, figs. 5; ahs. in Jour. Chem. Soc. [London], 108 

 {1915), No. 629. I, p. 109). — Employing essentially the same method used in the 

 work above noted, in order to test the behavior in this connection by hydro- 

 chloric acid, the author found that this acid produces at first a rapid decrease in 

 permeability. This is quickly followed by a rapid increase, the latter continu- 

 ing until the death point of the plant is reached. 



Antagonism between acids and salts, W. J. V. Osterhout {Jour. Biol. Chem., 

 19 {1914), No. 4, pp. 517-520, fig. 1; ahs. in Jour. Chem. Soc. [London], 108 

 {1915), No. 629, I, p. 109). — Employing the material and method above noted, 

 the author found that the degree of antagonism between sodium chlorid and 

 calcium chlorid was greater than that between sodium chlorid and hydrochloric 

 acid. Life was maintained longer in the most favorable proportions of the former 

 pair than in those of the latter. 



The results observed are held to afford evidence that the plasma membrane in 

 plants is protein in character. 



Physiological conditions in the large kelps of the Pacific Coast, G. B. Rigg 

 {Abs. in Science, n. ser., 42 {1915), No. 1094, p. 878). — On account of attention 

 being called to kelps as a source of potash fertilizer, the author has made an 

 investigation of the physiological processes of a number of the rapidly growing 

 species. The rapidity of growth is considered as favored by mechanical stretch- 

 ing by tidal currents, great turgidity due to high osmotic pressure in the cell 

 sap, and an abundance of potassium influencing nuclear division. 



It is said that there is more potassium than sodium in kelps, although the 

 reverse is true of sea water. This is believed to be possible because of the 

 greater permeability of the tissues for potassium and the change of potassium 

 compounds into some other form which does not lower the diffusion gradients. 



Attention is called to the differences of opinion as to the source and compo- 

 sition of the gases in the floats of marine algse. The author expresses the 

 opinion that the carbon dioxid for photosynthesis comes from either the gas 

 in these floats or the carbonates in the sea water, rather than from the car- 

 bon dioxid of this water. Tidal currents are considered a factor in photosyn- 

 thesis by keeping the fronds at the surface. The kelps are said to produce no 

 starch, but their sugars may be a factor in the high osmotic pressure. 



Quasi-experimental formation of ascidia in cotton leaves, F. E. Lloyd {Abs. 

 in Science, n. ser., 42 {1915), No. 1094, P- 879). — The author reports growing 

 small cotton plants in pots for more than a year which were subjected to se- 

 vere physiological drought. Plentiful watering, aided by rising temperatures, 

 resulted in forcing growth and the production of a large proportion of abnor- 

 mally shaped leaves culminating in perfect ascidia raised on their proper 

 petioloid supports. Such abnormalities are considered to rise from identical 

 conditions with fasciations. 



