AGRICULTURAL BOTANY. 931 



Relative transpiration in cacti, B. E. Livingston (Plant World, 10 (1907), 

 No. 5, 1)1). llO-ll.'f, fig. 1). — The author has stiuliecl the curves of relative trans- 

 piration for a number of leafy plants and for several forms of cacti. The 

 curves for the leafy plants agree in having uniformly a high period in the day 

 and a low one in the night, while the curves for the cacti exhibit the opposite con- 

 dition of affairs. Of 26 experiments with 8 species of 3 genera of cacti, 84 

 per cent were in agreement with the above statement, while tlie others showing 

 erratic variations were believed to be pathological specimens. 



The author states in conclusion that from the observed facts it seems clear 

 that there exists in the cacti a mechanism for governing the rate of water loss, 

 which is entirely different in its response to external conditions or in its daily 

 periodicity from the corresponding mechanism in leafy plants. 



The relation of injury to fasciation in the evening primroses, Alice A. 

 Knox (Plant World, 10 (1907), No. 7, pp. l-',5-151, fig. 7).— A form of fasciation 

 of the evening primrose due to attacks of a moth is described. 



A study of the carbohydrate metabolism in the sugar beet, S. Stbakosch 

 (ZtscJir. Vcr. Dctit. Ziickvrindus., 1907, No. 623, II, pp. 1057-1068) .—The 

 author has made a study of the carbohydrates as they appear in the sugar beet 

 and their various transformations. He claims that dextrose is formed in the 

 mesophyll of the leaf blade and that no other kind of sugar is to be found in that 

 part of the leaf. The transfer of dextrose to the veins of the leaf follows the 

 appearance of levulose in the veins. Cane sugar is found in the veins of the 

 leaf after the presence of levulose is noted. The transformation of the mono- 

 saccharids to cane sugar in the leaf is dependent upon light, and it ceases imme- 

 diately when the leaf is placed in darkness. The formation of starch in the 

 chlorophyll grain takes place after the formation of cane sugar and only after 

 there has been a consideraltle accumulation of carbohydrates in the mesophyll. 



The proteases of plants, IV, V, S. H. Vines (Ann. Bot. [London^, 20 (1906), 

 No. 78, pp. 113-122; 22 (1908), No. 85, pp. 103-113) .—In continuation of previous 

 studies (E. S. R., 17, pp. 542, 750) the author gives an account of experiments 

 with seeds. 



In the series covered by the first paper the seeds used were those of various 

 species of beans, peas, lupines, and maize. All of the seeds except the lupines 

 were starchy, and it was found that the ungermiuated seeds contained a pro- 

 tease that acted immediately on Witte-peptoue, and one or more proteases that 

 acted more or less slowly upon the reserve proteids of the seeds; further, that 

 the germinated seeds all contained a protease that digested fibrin and that such 

 a protease in certain cases developed in the substance of the ungermiuated seed 

 during the experiment. 



In the second series of experiments the author confined his attention to oily 

 seeds, especially those of hemp, but also of mustard, hazel, castor-oil plant, and 

 flax. It was found that oily seeds were much more proteolytically active 

 than starchy seeds. All the oily seeds investigated either contained to begin 

 with, or developed during the experiment, proteases that effected both peptoni- 

 zation and peptolysis, and proved more active than those in starchy seeds. 

 There was found a serious difficulty in comparing seeds, as there was no means 

 of knowing the relative ages of the different samples. 



Experiments were conducted on the separation of the proteases, the details of 

 which are given, and the author believes that he succeeded for the first time in 

 isolating from a vegetable tissue a protease that is essentially peptic in its prop- 

 erties. His investigations seem to warrant the conclusion that the hemp seed 

 contains two jirotoascs. one a ]K'ptase, the other an ereptase. 



The presence of peroxidase in dry seeds, Brocq-Rousseu and E. Gain 

 (Compt. licnd. Avud. tSci. [rarits], 1J,5 (1907), No. 25, pp. 1297, 1298).— A study 



