522 EXPEEIMENT STATION RECORD. 



luatic end, where the fecumlity iii;iy be oven lower than it is a little farther 

 down in the pod. 



Variation of structure and color of flowers under insolation, H. E. Rawson 

 {Abs. in Rpt. Brit. Ahhog. Adv. Sci., 1913, pp. 711-713). — In pursuance of work 

 previously noted (E. S. R., 21, p. 319), the author reports studies with nas- 

 turtium under controlled conditions as regards illumination, employing in addi- 

 tion to the descendants of South African plants previously used some grown 

 from English seed. 



Very decided changes in the coloring pigments are apparently accompanied 

 by a tendency to sterility. A correlation is suspected between color of stem 

 and that of subsequent flowers. The occurrence of faseiation is now common, 

 as are also 'modifications in the mode of inflorescence. Plants of dwarf habit 

 have appeared and have been propagated for three generations by screening, 

 the unscreened seedlings soon reverting to the climbing habit. By permitting 

 cross fertilization and by limited employment of screening it is said to be 

 now easily possible to produce slight degi'ees of color modification. Certain 

 stiHictural characters which appeared have been transmitted. The sun's alti- 

 tude, diurnal or seasonal, seems to produce not only in coloration, but also in 

 metabolism, changes which can be reproduced in other individuals. 



Adjustment to lig'h.t in oats, W. H. Akisz {K. Akad. Wetensck. Amsterdam, 

 Yersl. Wis en Natuurlc. Afdccl., 22 {1913), pt. 1, pp. 536-5^9; also in ditto, 

 Proc. Sect. Sci., 16 {1913-U), pt. 2, pp. 615-628).— A study was made of oat 

 plants grown in a dark room so regulated as to be maintained at a constant 

 temperature and with varying illumination to determine the adjustment of 

 the plant to difiierent amounts of light. 



The observations with bilateral illumination showed that by illuminating a 

 plant, first on one side and then on the other, each stimulus results in a curva- 

 ture, as long as there is a certain definite time intervening between the two 

 exposures. If the illumination on the two sides should be simultaneous the 

 tendency to curve would be neutralized and consequently the plant would grow 

 in a straight line. Where the illumination was from all sides the growth 

 showed a condition that is considered the summation of unilateral illuminations. 



Electromotive phenomena in plants, A. D. Waller et al. {Rpt. Brit. Assoc. 

 Adv. Sci., 1913, pp. 2-'f 1-258). — The authors, referring to the tests and conclu- 

 sions reported by Balls (E. S. R.. 29, p. 27) as bearing upon their own work 

 (E. S. R., 28, p. 731), state that previously they themselves haVe applied the 

 test quantitatively only in selected cases. The present report contains a de- 

 tailed account of work carried out recently to sers-e as an indication and 

 sample of the procedure considered necessary in working out the test as a 

 practical method of measuring the vitality of seedlings. Their data are held 

 to indicate a general relation between plant vitality and voltage of blaze 

 curx'eut. 



On the regulation of the transpiration of Viscum album and Rhipsalis 

 cassytha, Z. Kamerling (E. Akad. Wctensch. Amsterdam, Tersl. Wis en 

 Natuurk. AfdecL, 22 {1913-1^), pt. 2, pp. 821-835, pi. 1; also in ditto, Proc. 

 Sect. Set., 16 {1913-U), pt. 2, pp. 1008-1021, pi. i).— Results are given of a 

 study on the antagonism between the guard cells of the stomata and the ad- 

 jacent cells of the epidermis in these plants. 



It was found that in leafy boughs or whole plants allowed to wither the 

 amount of transpiration per unit of time remains approximately constant 

 until the bough is dried up, or the amounts decrease uniformly until tx'anspira- 

 tion is reduced to a minimum. In the study of the two parasitic plants 

 enumerated above it was found that when they had lost a certain proportion 



