424 EXPEKIMENT STATION KEOORD. 



Chlorophyll assimilation through cork, Mathilde Goldflus {Rev. Gen. Bot, 13 

 {1901), No. 146, pp. 49-92, ph. 2,fig.^. S). — A detailed report is made upon experiments 

 in which the author sought to ascertain the effect of a cork layer on the photosynthesis 

 of plants. The stems of a large number of plants were examined, in which there 

 was a well-developed layer of chlorophyll parenchyma underlying the bark. Sec- 

 tions of these were placed in a special apparatus, the amount of carbonic acid in the 

 atmosjihere determined before respiration began, and again at periods of 12 hours. 

 About 20 species of woody plants were examined. Chlorophyll is distributed 

 more or less through the branches of most trees and frequently occurs in their trunks, 

 but is there limited to the region where the cork layer is more or less ruptured and 

 furrowed. The author found that there was considerable assimilation in the sec- 

 tions of stems examined, and as the chlorophyll does not disappear from these 

 regions during the winter its functions are probably continuous throughout the year, 

 as there seems to be nothing to indicate a winter resting stage. 



Are the lower chlorophyll-bearing algae able to assimilate atmospheric 

 nitrogen? "W. KkIjger and W. Schxeidewind {Landv. Jalirh., 29 {1900), No. 4-5, 

 pp. 771-804, pis. 3). — The authors report extensive experiments with several species 

 of Stichococcus, Chlorella, and Chlorothecium, in which their ability to assimilate 

 atmospheric nitrogen, when grown in pure cultures and sterilized media, was tested. 

 As a result of the experiments, the authors claim that without the presence of com- 

 bined nitrogen, either in organic or inorganic form, there was but slight develoi)ment 

 of the different sijecies of algse; while if the substratum, upon which they were grown, 

 contained combined nitrogen they made abundant growth. There appears to be 

 nothing to indicate that these algfe are able to fix the atmospheric nitrogen. Green 

 algpe, according to their investigations, are unable to assimilate the free nitrogen, and 

 when experiments are conducted that appear to show an increase in the nitrogen con- 

 tent, it is explained by the fact that the algae offer conditions very favorable for the 

 development of soil and other bacteria which are able to assimilate atmospheric 

 nitrogen. 



Concerning the modifications of structure produced in vegetable cells by 

 freezing, plasmolysis, and ■wilting, L. Mateuchot and M. Molliard {Compt. 

 Rend. Acad. Sci. Parts, 132 {1901), No. 8, pp. 495-498).— A. study of the effect of 

 freezing, plasmolysis, and wilting upon the leaves of Narcissus, and some other plants 

 shows that the conditions produced by each of these phenomena are identical. 



The effect of temperature and oxydizing enzyms on the formation of transi- 

 tory starch, J. Gruss ( WcJiDSchr. Brau., 1899, No. 40; ahs. in Bot. Ceritbl, 85 {1901), 

 No. 1, i)p. 8-11; also in Jour. Roy. Micros. Soc. [London'], 1901, No. 2, p. 181). — In 

 experiments with germinating barley, the author found that the formation of transi- 

 tory starch began at a temperature of 0° C. and increased in the rapidity of forma- 

 tion until the optimum was reached at about 30° C. At 40° C. it was checked, and 

 ceased altogether at .50°. Intimately associated with the formation of transitory 

 starch was found an enzym to which the name spermase is given. Sucrose is said to 

 be the first car])ohydrate used during the germination of barley, and starch is not 

 utilized until the embryo attains a stage in its development when it is able to furnish 

 the enzyms necessary to render the starch available. The rootlets of the young plant 

 are said to be inclosed for a time in a kind of gum which is believed to be some form 

 of galactan, and it contains a liquefying enzym. 



Concerning the occurrence of cane sugar in plants, J. Anderssen {Ztsckr. 

 Physiol. Chem., 29 {1900), No. 4-5, pp. 423-428). — The author identified cane sugar 

 in the rhizome of Aspidmm felix mas and A. spinulosum, and other ferns. 



The effect of germination on the pentosans in seeds, A. Schone and B. 

 ToLLENS {Jour. Lanchc, 48 {1901), No. 4, pp. 349-354). — An account is given of 

 experiments with barley, wheat, and peas, in which the effect of germination upon 

 the pentosans in the seed was investigated. Instead of being a loss m pentosans. 



