626 EXPERIMENT STATION EECORD. 



As a result of the investigations, ttie author claims that no more than 0.62 

 lb. borax or 0.75 lb. calcined colemanite should be added as a larvicide to each 

 10 cu. ft. of manure, and that when using the boron-treated manure in growing 

 leguminous plants it should be thoroughly mixed with untreated manure 

 before being added to the soil. \\'ith other plants, boron-treated manure should 

 not be used at a higher rate than 15 tons per acre. 



The influence of the radiations of radium upon the germination of seeds 

 (oats), H. LA^\•KE^•CE (Rpt. Austral. Assoc. Adv. ScL, 14 (1913), pp. 325. 326}.— 

 The author's experiments are said to have shown the total destruction of oat 

 seeds exposed to radium emanations at distances not greater than 0.75 in. Be- 

 yond that limit there was a decrea.se with the increasing distance of the retard- 

 ing effect of radium upon the growth of the seeds, and the development of a 

 stimulating effect at greater distances up to 5 in. 



Some effects of ethylene on the metabolism of plants, E. M. Harvey {Bot. 

 Gaz., 60 (1915), Xo. 3, pp. 193-21^, figs. 2).— The author, reporting a study of 

 pea seedlings in this connection, states that ethylene was found to be very 

 effective, even in attenuated solutions, in producing changes in the general 

 processes of plant metabolism. The simple soluble substances were increased 

 at the expense of the higher soluble and in.soluble forms. The acidity of the 

 tissue treated with ethylene remained unchanged. Ethylene caused an increase 

 of osmotic pressure, but did not gi'eatly increase permeability. It retarded 

 both carbon dioxid production and oxjgen absorption. The respiratory ratio 

 remained practically the same, except in the shortest exposure period (three 

 hours) in which, apparently, an excessive production of carbon dioxid occurred. 



A bibliography is given. 



The rate of absorption of various phenolic solutions by seeds of Hordeum 

 vulgare, and the factors governing' the rate of diffusion of aqueous solutions 

 across semipermeable membranes, A. J. Brown and F. Tinker (Proc. Roy. 

 Soc. iLondon], So: B, 89 (1915), Xo. B 611, pp. 119-135, figs. 4).— A further 

 study (E. S. R., 28, p. 226) of the phenomena of diffusion through seed coats 

 of H. vulgare, employing phenolic solutions, has led to the conclusion that 

 when the osmotic pressures, vapor pressures, and viscosities of a series of 

 solutions of permeable solutes are equal, their rates of diffusion through the 

 barley membrane are inversely proportional to their surface tensions. 



Chemistry and structure of plant cell membranes, .1. Konig and E. Rump 

 (Chcmie vnd Struktur dcr Pflanzcn-ZeUmemhran. Berlin: Julius Springer, 

 1914, pp. 88, pis. 9, figs. 8). — Besides an extended historical introduction, an 

 account is given of studies by the authors on the chemical composition, micro- 

 scopic structure, etc., of cell membranes from a number of plants. 



It is stated that the chemical substances left in the cell membranes after 

 the removal of the protein, fat, wax, chlorophyll, sugar, starch, acids soluble 

 in water, and cutin, fall particularly into the pentosan, hexosan, and lignin 

 groups. Microscopic studies are said to show the incorrectness of the view that 

 a chemical union exists between cellulose and the substances associated there- 

 with. 



Studies in experimental morphology. H. LvndegArdh (Flora, n. ser., 7 

 (1915), No. 4, pp. 433-449, figs, i^).— The author describes the results of a study 

 on the polarity of Colcus hybridus, and on leaf heteromorphy in Ipomoea leari 

 with corresponding alterations in the anatomy of the stem. 



Autoparasitism of Cassytha melantha, A. D. Hardy (Rpt. Austral. Assoc. 

 Adv. Sci., 14 (1913), pp. 321-324, pi. i).— Noting observations made upon C. 

 vielnnthn, the author states that frequently when a branch of the plant has 

 outgrown the twig on which it is parasitic and failed to find another or a new 



