BOTANY. 635 



fied for the various conditions under whicli they secured polhnation. As a rule 

 those famiUes of plants in which cross fertilization is usual lunc stii;nias bearing a 

 marked similarity throughout the group. 



The morpholog'y and physiolog-y of the germination of Spermaphytes, 

 A. J. J. Vandevei.dk { A' kiciiiiiKj ili'r ZditdphDitt'ii, iiiorjiho/Di/lr cii pJij/aiologie. (Uwnt: 

 J. Vuijhteh', 1900, pt.2,pp. 137-SOl, Jigx. 28).— Va,rt 1 of this work, which apj^eared in 

 1897 (E. S. R., 9, p. 526), was mostly taken up with a bibliography of the subject. 

 In the present contribution the morphology of germination is discussed at consider- 

 al)le length, as is also the j)hysic8 and physiology. The bibliography quoted in the 

 first part is added to, and reviews are given of the extensive literature relating to 

 this subject. 



Studies on tuber formation, N. Bernard {Rev. Gm. BoL, 14 {1902), Nos. 157, 

 pp. 5-25; 158, pp. 58-71; 159, pp. 101-119; 160, pp. 170-183; 161, pp. 219-235; 162, 

 pp. 269-279, ph. ,?).^-The author designates by the term tuberization the special 

 development which is characterized by the slow morphological and histological 

 differentiation of vegetative points of growth or buds, and which serve for the storing 

 up of reserves not utilized by the differentiation. He has examined quite a number 

 of species of orchids, ranunculus, potatoes, and other tuber-forming jilants, and finds 

 their roots normally infested with filamentous fungi which are apparently of the 

 genera Nectria, Hypomyces, and others. On account of the constant presence of 

 the fungi the author believes that they are a requisite to the formation of tubers He 

 has divided the different methods of tuber formation into 3 categories: Precocious 

 tuberization, in which the infection of the plant takes place at the tiuie of germina- 

 tion and continues throughout the life of the plant; tuberization which is preco- 

 cious and periodic, in which there appear to be alternate perio<ls of infection and 

 noninfection; and late jteriodic tuberization, in which the infection is not realized 

 until a considerable time after germination. This last forui is the one observed in 

 the case of the [)otat(^, the others I>eing illustrated by various species of orchids. 



Electric response in ordinary plants under mechanical stimulus, J. C. Bose 

 (./n(/r. Lhm. Soc. [Lo7idon], Bot., 35 {1902), No. 245, pp. 275-304, figs. 25).— \ series 

 of exjjeriments was conducted to determine whether the response phenomena showed 

 a parallelism between animal and vegetable life. It was desired to ascertain the 

 relation between the intensity of stimulus and the corresponding response on the 

 ])art()f the jilants, and the effect of various stimuli such as chemicals, temperature, 

 ana'sthetics, etc. The experiments were conducted upon the roots, stems, leaf- 

 stalks, flower stalks, and fruits f)f a number of plants, and the results obtained indicate 

 that the electric record gives an unfailing indication of the modification of the 

 plants' vitality underthe influence of various external agencies. The electric response 

 is shown to be a faithful index of physiological action, and the response was found 

 to be modified by any influence which affected the vitality of the plant. 



A method of investigating the gravitational sensitiveness of the root 

 tip, F. Darwin {Jour. L'nm. Soc [London], Bot.,35 {1902), No. 245, ]tp. 266-274, figs. 

 9; ah.<t. iji. BoL f evil >L, 90 {1902), No. 11, p. 295).— A method is described lor investi- 

 gating the sensitiveness of the root tip of plants to the infiuence of gravity, which 

 consists of fixing the root tip by means of a tube in a horizontal position so that 

 the cotyled()ns and hypocotyl are free to move. These organs are so supported by 

 a counterbalance that when geotropic curvature of the root begins, the cotyledons 

 move, in some cases traveling through as much as a 180° arc. The experiments 

 showed that there was a strong tendency in the case of the root of the bean and 

 pea to continue curving when the tip was tixed horizontally and the other end of 

 the seedling was free to move. The results obtained are based on the assumption 

 that the tip is the only part of the root which is sensitive to gravity. 



Root pressure in Begonia, J. B. Dandeno {Sdenee, n. ser., 16 {1902), No. 412, 

 pp. 833-835). — An account is given of experiments with a vigorous growing begonia 



