AGRICULTURAL BOTANY. fi51 



solubility of the phosphoric acid, the increase being especially marked in the case < >i 

 nitrate of Boda. 



Inspection and analyses of commercial fertilizers on sale in the State, \\ . 

 !•'. Hand est \i. [Mississippi Sta. Bui. 91, pp. 54)- This bulletin gives tables of 

 analyses of fertilizers inspected during the season of 1904 5, being the fourth publica- 

 tion of analyses of samples of fertilizers drawn during thai season. 



AGRICULTURAL BOTANY. 



The sensitiveness of the chlorophyll of plants tolerant and intolerant to 

 shade, W. Lubimbnko ( Rev. Gin. Bot., /; I 1905), No. 901, pp.381 415, pis. 9, fig. t).- 

 Experiments are reported in which the author sought to establish the minimum of 

 lighl intensity required for carbon dioxid decomposition by a number of species of 



plants. 



The subjects of the experiments were Scotch pine and birch representing intolerant 

 species, and fir and linden as those tolerant of shade. The choice of these species 

 was made so that the results obtained with the evergreen trees would be comparable, 

 as would also those obtained with the deciduous species. These different trees were 

 observed under artificial conditions of light and under natural conditions of very 

 diffused light, strong light, and full sunlight. 



For the intolerant species the average results show that the energy of carbon 

 assimilation increases with the intensity of light, while for the tolerant species there 

 is an optimum which corresponds to the angle of inclination of the leaf surface to the 

 sun's ray-. 



Summarizing his investigations the writer concludes that the curve of photo- 

 synthesis may be determined from the anatomical structure of the leaf and from 

 specific qualities of the chloroplasts. The influence on the anatomical structure may 

 be seen through all degrees of illumination. Of the species studied the birch and 

 linden assimilated more carbon dioxid per unit of leaf weight than the pine and fir 

 under conditions of average illumination. The specific qualities of the chloroplasts 

 predominated where the illumination was very feeble or very intense. The tolerant 

 species, linden and fir, began assimilation with much less illumination than the 

 intolerant birch and pine. In the mote intense light the assimilation of the tolerant 

 species decreased, while for the intolerant ones it continued to increase with the 

 illumination. 



A microscopic examination of the leaves showed that the chlorophyll grains of the 

 tolerant species were decidedly larger than those of the intolerant varieties. A spec- 

 troscopic examination of alcoholic solutions of the chlorophyll of the leaves showed 

 important differences, the spectra and curves of absorption being almost in direct 

 relation to the carbon dioxid decomposition. The author, in conclusion, says that 

 the terms tolerant and intolerant should he considered with reference to the carbon 

 dioxid decomposition of the species. The leaves of intolerant species require more 

 light in order to compensate for their greater respiration. 



The influence of sunlight and diffused light upon the leaf development of 

 deciduous trees and shrubs, J. Wiesneb [SUzber. A'. Akad. Wiss. [Vienna], Math. 

 Naturw. Kl., US [1904), No. 8-9, pp. /H9-494).— In continuation of his photometric 

 investigations, the author describes experiments with Robinia pseudacacia, Amorpha 

 fruticosa, and Broussonetia papyrifera grown in full sunlight and in varying degrees of 

 diffused light, the object being to determine the minimum of light required by these 

 plants for the beginning of leaf development and for sustaining it throughout the 

 growing season. 



Regeneration in roots, B. Nembc [Studien iiber die Regeneration. Berlin: Born- 

 traeger Bros., 1905, pp. 387, figs. ISO; rev. in Nature [London], 73 (1905), No. 1886, 

 pp. 170, 171). — This volume gives the results of investigations carried on to throw 

 some light upon the nature of the processes of regeneration, the causes that initiate 



