22 EXPERIMENT STATION RECORD. 



magnesia, and potash content of roots, stems, cotyledons, endosperm, etc., were 

 determined. The results of the analyses were discussed at length, the analytical 

 data being given in detail. 



The influence of light during germination on the assimilation of organic 

 reserve material in seeds and bulbs, W. Lubimenko (Compt. Rend. Acad. Hci. 

 [Pitri.s]. lU (1907), yo. 19. pp. 1060-1063. lUjin. i).— Wheat, oats, peas, white 

 lupines, maize, and onions were grown under bell jars and the amount of light 

 was regulated by covering the glass with varying thicknesses of white or black 

 paper. The total growth, length, fresh and dry weight, etc.. of the plants in 

 each series was ascertained. The weight for the dry plants, grown under the 

 different lights and intensities, is shown by curves from which it appears that 

 while the water content varied but slightly, the dry weight of the different 

 plants varied widely, depending upon the amounts of illumination. 



The wheat, maize, pea. and onion plants increased in dry weight with in- 

 creased illumination up to a maximum which about corresponded with the 

 amoiuit of light necessary for the beginning of chlorophyll formation. The 

 dry weight of the wheat, peas, and onions grown in diffused light was greater 

 than when grown in partial shade, but with maize, white lupines, and oats the 

 dry weight was greatest for those plants grown under less light, and for lupines 

 and oats the maximum dry weight was correlated with a minimum of light. 

 The author concludes that the assimilation of reserve material stored in seeds 

 and bulbs is influenced by the amount of light and that assimilation attains its 

 maximum at about the amount of illumination required for the formation of 

 chlorophyll. An increased illumination beyond this optimum is followed by 

 diminished assimilation. 



The development of chlorophyllous plants in the absence of carbon dioxid 

 but with nontoxic quantities of amids, .1. Lefevre (Her. Gen. Bot.. 18 {1906}, 

 A'o.s'. 20S, pp. i-JJ-itfJ, flu. 1; 209, pp. 205-219; 210, pp. 258-280, figs. //; 211. pi). 

 302-310). — A series of experiments was conducted with cress and sweet basil 

 grown in pots under bell .jars without carbon dioxid but in the presence of a 

 number of amids. The plants were supplied with chemical fertilizers to which 

 was added a mixture of tyrosin, oxamid, glycocoll, alanin, and leucin at the 

 rate of 1.1 gm. for every 500 gm. of soil. 



The plants were observed under conditions of light and darkness, and it was 

 found that in the presence of sunlight they were able to make considerable 

 growth, attaining in (i weeks a size fully 10 times that of the original, and with 

 well-developed foliage and flower Ijuds. As this growth took place in the entire 

 absence of carbon dioxid, the carbon required must have come from the amids 

 and was taken up by the roots. That the transfer was not simply osmotic, but 

 true synthesis, is shown by the absence of all, or nearly all, growth when the 

 plants were kept in the dark. Apparently photosynthesis took place in almost 

 normal amount. 



Carbonic acid assimilation and chlorophyll function, F. G. Kohl (Ber. 

 Dent. Bot. GeselL. 2) {1906), GeiieralversannnlHiigs-Heft, pp. 39-5-'i). — A resume 

 is given showing the present status of our knowledge relating to the assimilation 

 of carbon dioxid and the chloroiihyll function of plants. 



The function of invertase in the formation of cane and invert sugar dates, 

 A. E. Vinson {Bot. Gaz., ^3 {1907), No. 6, pp. 393-407).— In the studies made at 

 the Arizona Experiment Station on the ripening of dates, the author has found 

 that different varieties of these fruits have decidedly different chemical compo- 

 sition and that there appear to be well-established chemical mutants among date 

 palms. These mutants originated long ago and are perpetuated by suckers. 

 Whether they will transmit their differences through seedlings remains to be 

 demonstrated. 



