AGlirt'ULTiniAL BOTANY, 1123 



snhject to radical dinVronces in nianuriiii;. The ivi)ut»Ml difference in strength 

 between jrrains of tlie same variety jrrown under identical conditions, but cut 

 jjcreen and dead ripe, is not associated with any significant cytoiogical change. 



Examination of the different grades of flour obtained during the various 

 processes of roller milling shows that the cells of the aleurone layer very 

 rarely get into the flour, but remain attached to the bran. The endosperm of 

 the seed during its development arises in the first place by free cell formation, 

 but after about a week wall formation begins, starting from the periphery of 

 the embryo sac and proceeding inward. The peripheral layer is marked off 

 about two weeks after pollination, and develops into the aleurone layer. The 

 deposition of starch grains begins in the middle of the flanks of the endo- 

 sperm at the lower end of the grain and proceeds upward and outward. 

 Reserve nitrogenous materials enter at the same time as the starch. During 

 the i)rocess of ripening a disorganization of the endosperm nuclei takes place, 

 caused by the increasing pressure of the surrounding food stuffs. The nuclei 

 lose their nucleoli, become deformed, and. finally appear as a fine network 

 spread out between the intruding starch grains. 



A study of the develoi)ment of the embryo was made, and it was found to 

 be normal, but a fifth lateral rootlet is said to be formed in addition to the 

 two pairs of laterals usually desc ril)ed. 



The presence of amylase in old seeds, Brocq-Rousseu and E. Gain (Compt. 

 Rend. Acad. Sci. [Paris^. l',S (IDOD), No. 6, pp. 3'}9-26l).— In previous ac- 

 counts (E. S. R., 20, p. 130), the authors have shown that the duration of 

 diastases in seeds is limited. In the present report the results are given of a 

 study of wheat taken from museum specimens that are known to be 50 

 years old. 



In this investigation dextrinase and amylase were found pre.sent and still 

 capable of transforming starch into sugar. The experiments did not permit 

 of definite conclusions as to whether the diastatic action w.is retained with its 

 initial power for the entire period. They confirmed the conclusion, however, 

 that the power of germination in seeds is not entirely due to the action of 

 certain diatases, as the seeds in no case would germinate although the diastase 

 was present. 



The presence of oxydases in india rubber, D. Spence (Bio-Chcm. Jour.. 3 

 (IDOH), Nos. .',, pp. la.'j-isi ; 6-8, pp. 351, 352).— A study has been made of the 

 latex of Para rubber trees and also of fresh latex from Finitiouia ('lastica, 

 from which the author is able to show the presence of oxydases in the latex. 

 He believes that the darkening in color of raw rubber is due to an oxydase 

 which is as.sociated with the protein or the so-called insoluble constituent of 

 the rubber. Further experiments are to be carried on to determine how far 

 the oxydase is resi)onsible for certain other changes occurring in raw rubber, 

 such as decomposition, oxidation, and the like. 



The second paper reports an examination of 4 separate samples of latex from 

 Hcvca brasiliciisis. I'ara rubber, in each of which was found evidence of the 

 l>resence of an oxidizing enzym, the chemical properties of which have not yet 

 been studied. 



The author suggests that the caoutchouc is probably a reserve food material 

 for the plant, and that to account for its formation and subsequent decomposi- 

 tion the presence of oxidizing eiizyms must be considered. 



Relation of plant growth and vegetation forms to climatic conditions. 

 J. J. TiioKNriEK (I'hnit World, Li it!KHI), \o. I, pp. 1-1). — An account is given 

 of studies on the relation of plant growth to climatic conditions in different 

 parts of Arizona, jiarticnlar attention being given to winter and sununer annu- 

 als. The author claims that on account of temperature conditions, it is impossi- 



