AGRICULTURAL BOTANY. 325 



may, by isomerism, become colorless, it is suggested that such a change may be 

 instrumental in producing the white flowers, but this has not yet been estab- 

 lished. 



The localization of potash compounds in the sugar beet and their physio- 

 logical relation, A. MatouSek {Ztschr. Zuckerindus. BiJhmcn, 88 (1914), No. 5, 

 pp. 235-251, figs. 6). — ^The author reports that potash salts are to be found in 

 the embryo of the sugar beet seed. In the plant potash is widely distributed, 

 being most abundant in the leaf blade, less so in the petiole, and least in the 

 roots. In the blade of the leaf potash is more abundant in the portions beneath 

 the upper epidermis. The xylem part of the fibrovascular bundles in leaves, 

 roots, etc., has a higher content of potash than the phloem. In the root the 

 potash content is highest in the upper part, particularly in the corky portions, 

 and tends to increase in the vicinity of any wounds. In water cultures, in the 

 absence of potash in the nutrient medium, potash is found in the blade of the 

 leaf, the roots containing practically none. Etiolated leaves have a very low 

 content of potash, and the general distribution of potassium compounds in 

 etiolated plants, as well as those grown with a limited amount of potash, is 

 similar to that in normal plants. 



Comparative studies on tropisms. — VI, Influence of alkalies and alkaline 

 earths on Lupinus albus, T. M. Porodko (Bcr. Deut. Bot. Gescll., 32 U914), 

 No. 1, pp. 25-35, fig. i).— Previous worli, mainly qualitative (E. S. R., 25, p. 632) 

 regarding the effects of solutions on tropisms, has been followed by studies on 

 the responses, quantitatively considered, of white lupine seedlings tested with 

 solutions of alkalies and alkaline earths in different strengths. The results are 

 given in tabular detail. 



The action of certain compounds of zinc, arsenic, and boron on the growth 

 of plants, WiNiFEED E. Brenchley {Ann. Bot. [London'\, 28 {1914), No. 110, 

 pp. 283-301, figs. 17). — Results are given of water culture experiments of peas 

 and barley in which the action of zinc sulphate, arsenic compounds, and boric 

 acid was tested. 



Zinc sulphate in high concentrations was found very toxic to barley and 

 peas and no evidence of stimulation was obtained even when as great a dilu- 

 tion as 1 to 200,000,000 parts was used. Arsenious acid was found more toxic 

 in its action on i>eas and barley than arsenic acid. This distinction also held 

 good for sodium arsenite and sodium arsenate. No stimulation was observed 

 even with the smallest quantities tested. Boric acid was found less poisonous 

 than zinc sulphate or arsenic compounds, especially with peas. Barley showed 

 some evidence of stimulation with the weaker strengths of boric acid, but this 

 was not borne out by an examination of the dry weights. Peas, on the other 

 hand, were definitely stimulated with relatively high concentrations of boric 

 acid. Where the higher strengths of this poison were used the action was 

 quite evident, the leaves tending to become brown and to die in a character- 

 istic manner. 



Recent studies on diffusion and localization of ions in plant tissues, C. 

 ACQTJA {Atti R. Accad. Lincei, Rend. CI. Sci. Fis., Mat. e Nat., 5. ser., 22 {1913), 

 II, No. 11, pp. 594-598). — In extension of work previously noted (E. S. R., 30, 

 p. 31), the author tested the effects upon development of seedlings exerted by 

 cerium. 



It was found that development, especially of the root system, of Triticum 

 sativum is quickly checked by cerium chlorid in very dilute solution, no sec- 

 ondary roots being formed in the cases observed. Microscopic examination 

 showed a yellow deposit Jn the cortical cylinder of the roots, which increased 

 and finally occupied in part the intercellular spaces. These results, agreeing 

 with those pre\iously noted when employing manganese, uranium, and lead, 



