306 PHYSIOLOGY [BoT. Absts., Vol. VII, 



such a solution was supplied through the cut end of a side branch of a leafy shoot, downward 

 conduction of the salt in the main axis took place even below the leafy region of the latter. 

 The same result was observed even when there was an abundant supply of water from below, 

 and in the absence of any pull by transpiring leaves. It was shown that the water channels 

 under normal conditions function independently of each other. This was particularly clear 

 when an eosin solution entered by a side branch. In such cases the staining in the woody 

 cylinder below the point of attachment of the branch was sharply limited to the side on which 

 the branch was attached. The downward movement observed was at a much lower rate 

 than that of the normal transpiration stream but reached 1 to 10 cm. an hour when a 1 per 

 cent lithium nitrate solution was used. The time required to transport a unit quantity of the 

 salt a given distance was from ^V to sijj of that required by living tissue. However, the 

 author doubts whether the ability of the wood to conduct dissolved substances downward 

 at certain times is sufficient to provide for the necessary downward transport of material 

 in the living plant. — R. M. Holman. 



2119. Pfeiffer, T., tJND A. Rippel. Uber den Einfluss von Durstperioden auf das 

 Wachstum der Pflanzen. [Regarding the effects of periods of drouth upon the growth of plants.] 

 Landw. Versuchssta. 96: 353-363. 1920.— Lupines, asparagus, barley, and oats were grown 

 under 2 sets of conditions as regards moisture content of the soil. In one case the moisture 

 content of the soil was maintained at 60 per cent of the water-holding capacity of the soil, 

 and in the other the plants were regularly allowed to go without watering until the moisture 

 content of the soil had fallen to about 30 per cent of its water-holding capacity, after which 

 it was again brought up to 60 per cent. This alternate lowering and raising of the moisture 

 supply was repeated up to harvest time. It was found that under the alternating periods of 

 drouth, crop production was decreased as follows: Lupines 20.5 per cent, asparagus 15.5 per 

 cent, barley 6.2 per cent, and oats 3 per cent as compared with the plants grown under a 

 constant, full supply of soil moisture. It is evident that different kinds of plants vary in 

 their ability to adapt themselves to varying moisture supply .^A. T. Wiancko. 



MINERAL NUTRIENTS 



2120. De Angelis d'Ossat, G. Ancora sul calcaree le viti americane. [American grapes 

 and lime.] Staz. Sper. Agrarie Ital. 53: 97-100. PL 2. 1920.— This is a short contribution 

 upon the subject of adaptation of Vitis Berlandieri, V. Candida, V. rupestris, V. riparia, 

 V. labrusca, and V. vinifera to various concentrations of calcium carbonate in the soil. The 

 conclusion is reached that the above mentioned species can develop normally and with no 

 symptom of chlorosis in soils the concentration of which in CaCOa is much greater than is 

 generally considered safe in practise. The calcimetric scale of Bonnet is found to be of very 

 little value. — A. Bonazzi. 



2121. Geilman. tJber die Verbreitung des Titans in Bbden und Pflanzen. [The distri- 

 bution of titanium in soils and plants.] Jour. Landw. 68: 107-124. 1920.^A method of deter- 

 mining the titanium content of soils is given, and its value tested. Analyses of a number of 

 soil samples showed that titanium is very widely distributed in soils, the content varying 

 from a trace to 1 per cent, with most of them showing from 0.3 to 0.6 per cent. Analyses of 

 plants showed titanium always present, the content being greatest in the green parts, and the 

 range being from a trace to 0.27 per cent.— C. E. Leighty. 



2122. Gile, p. L., and J. O. Carrero. Cause of lime-induced chlorosis and availability 

 of iron in the soil. Jour. Agric. Ees. 20: 33-61. PI. 5-8. 1920.— A brief review of ecological 

 studies of calciphilous and calcifugous plants, and of vegetative experiments in which 

 chlorosis has been produced by natural or artificial calcareous soils. — -Experimental data are 

 presented from which it is concluded that " 'lime-induced' chlorosis seems to be due simply 

 to a depression in the availability of iron in calcareous soils." Treatment of chlorotic rice 

 with a spray of ferrous sulphate shows that a lack of iron in the plant is at least one cause of 

 the chlorotic appearance. There is no evidence of a general "lime effect" inducing chlorosis.— 



