952 EXPERIMENT STATION RECORD. 



The investigation was carried <>n along the Potomac River at a number of locali- 

 ties, and from the survey made it is assumed that the salt water limit of wild rice is 

 approximately that represented by 0.03 of the normal solution of sodium chlorid. 

 This is considerably less than the concentration of the water of Chesapeake Bay and 

 probably indicates the maximum salt water resistance of the species in the regions 

 examined. Where less strengths of solution than this were observed the growth of 

 wild rice took place about in proportion to the strength of solution. It isalsostated 

 that the salt water limits of wild rice may be approximately determined by the sim- 

 ple test of taste. When water is appreciably salt to the taste it is too salt for the 

 successful growth of this plant. 



The assimilation of certain organic substances by chlorophyll-bearing 

 plants, P. Maze and A. Perrier (Ann. Inst. Pasteur, 18(1904), No. l .>, pp. 721-747, 

 pis. 2, figs. 11). — The authors report a preliminary series of experiments with maize 

 in which the assimilation of some organic substances was studied. The effect of the 

 different substances on the germination was investigated, as well as on the develop- 

 ment of the plants after having been germinated. 



Sugar, glycerin, methyl alcohol, and ethyl alcohol were found to retard the germi- 

 nation of maize for several days without wholly preventing the development of the 

 plants. When added to" solutions in which the plants are already growing sugars 

 are assimilated in darkness, but they are not able to supply the action of the sun in 

 photosynthesis. When added to culture media they are rapidly assimilated in sun- 

 light, and from the results of some of their experiments the authors conclude that 

 soluble organic substances in soils or solutions may aid in the growth of the chloro- 

 phyll-bearing plants. Where the plants were more advanced in growth glycerin was 

 absorbed in sunlight, but the growth of the plants was checked. Ethyl alcohol 

 proved somewhat injurious, which is believed to be due to the formation of aldehyde. 

 Methyl alcohol was readily taken up and it. is believed was assimilated by the plants. 

 The toleration of chlorophyll-bearing plants to the alcohols was exceedingly variable. 

 Some species seemed resistant to large quantities, but these compounds did not add 

 to the starch content of the plant while in the dark nor protect the starch already 

 occurring in the leucoplasts. 



The addition of dextrose to the. mineral solutions induced chlorosis in the plants 

 growing in them, and it is believed that this class of compounds may play an impor- 

 tant part in the occurrence of that disease. The authors experimented with plants 

 grown without iron, and attribute the chlorosis not so much to the absence of the 

 iron but to a superabundance of the alkaline bases, which render the iron less avail- 

 able or retard its action altogether. 



The action of sodium nitro-prussid on plants, R. Bahadur (Bui. Col. Agr. 

 Tokyo Imp. Univ., 6 (1904), No. 2, pp. 177-179).— The highly poisonous character of 

 nitro-prussid of sodium for animals has been demonstrated, and the author briefly 

 reports some experiments with various algae, fungi, and other plants to determine 

 whether it possessed the same poisonous property toward plants as toward animals. 

 It was found to be a comparatively weak poison for the lower animal organisms and 

 green plants, so long as daylight was excluded, and not to be poisonous to fungi at 

 all. The effect of daylight is to decompose the salt with the production of prussic 

 and nitrous acids. 



The effect of sulphurous acid, zinc oxid, and zinc sulphate on plants, E. 

 Haselhopf and F. Gossel (Ztschr. Pflanzenkrank. , 14 (1904), No. 4, pp. 193-201, pis. 

 2). — A report is given of pot experiments with wheat to test the effect of sulphurous 

 acid, zinc oxid, and zinc sulphate on the plants and soil. The soil used in the 

 experiments was a light sandy loam and fairly well supplied with the nutritive 

 materials required by the plants but rather deficient in lime. On this account 10 

 gm. of calcium carbonate was added to each pot in some of the series. Sulphurous 

 acid was passed into the soil and later the pots were all seeded to wheat. 



