1046 



EXPERIMENT STATION RECORD. 



author finds that of the species studied the reserve material consists of small quanti- 

 ties of reducing sugars, saccharose, mannan, and galactan. 



Formation of albumen by the biglier plants in tlie dark, I. Shulov {Izv. 

 Moscoto SelsJc. Khuz. In$t.. \_Ami. Inst. Agron. Moscoii], 8 {1902), pt. 4, /yj. 410-413). — 

 The experiments of the author were made with beets in glass vessels. In each ves- 

 sel, provided with sand fertilized with a mixture of nutritive salts (without nitro- 

 gen) , was planted 1 beet root. After 14 days 4 roots were taken out, 4 more after 

 24 days, 2 after 34 days, and 1 after 44 days, and the total nitrogen determined by 

 the Kjeldahl method and the albuminoid nitrogen after Stutzer. The results were 

 as follows: 



J'eldt'ion of (ilhint)'iiioid to liital nitrogen inplniils (/roirn. in llic dark. 



Total nitrogren 



Albuminoid nitrogen 



Proportion of albuminoid to total nitrogen 



Roots 



not 



sprouted. 



Per cent. 



1.255 



.560 



44. 620 



Sprouted roots, after- 



14 days. 24 days. 34 days. 44 days 



Per cent. 



1.700 



.805 



47. 350 



Per ce7it. 



1.620 



.820 



50. 620 



Per cent. 

 1.495 



58. 860 



Per cent. 



1. 820 



.945 



51.920 



These results seem, in the opinion of the author, to show beyond a doubt the 

 possibility of the formation of albumen by the green plants when growing in the 

 dark. — p. fire.man. 



The influence of organic materials on the development and structure of 

 certain plants, J. Laurent {Cumpt. Rend. Acad. Set. Paris, 135 {1102), No. 20, pp. 

 870-872). — A report is given of studies with peas, lentils, maize, and rye in which glu- 

 cose and glycerin were added to the culture solution in which the plants were grown. 

 It was found that if the solutions of glucose and glycerin were isotonic they gave 

 comparable results so far as the development and external characteristics of the 

 plants were concerned. The osmotic pressure not only produced modifications, but 

 each species exercised a specific influence. The diameter of the cells increased with 

 the osmotic pressure of the culture medium, the phenomena being most apparent in 

 the solutions of glycerin where the cells of the corticle parenchyma increased much 

 more rapidly and assumed a nearly spherical form. Solutions of glucose and saccha- 

 rose in general produced a thickening and lignification of the cells. The glucose 

 was not only used for the growth of the membranes, but also the reserve starch 

 which had accumulated in different parts of the tissues. The reserve materials were 

 found most abundant in those plants grown in cultures containing the glycerin; on 

 the contrary, the lignification was less noticeable and the differentiation of tissues 

 occurred much later. This is particularly true of the ligneous plants by which a 

 great part of the glycerin w^as absorbed and utilized. In the case of maize, starch 

 was not accumulated either in the roots or the stems and the glycerin was used 

 immediately. In this case the glycerin favored the thickening of the cell membranes 

 and lignification of the tissues. 



The germination of pollen in the presence of stigmas, P. P. Richer {Cornpt. 

 Rend. Acad. Sci. Paris, 135 {1902), N't). 16, pp. 634-636). — On account of its possible 

 bearing on the limits of the production of plant hybrids the author made a study of 

 the germination of pollen grains when in the presence of stigmas. A large number 

 of species were examined and it was found that many kinds of pollen which' could 

 not be made to germinate either in water or sugar solutions readily sent out their 

 pollen tubes if fragments of stigmas of the same or nearly related si)ecies were added 

 to the cultures. While a few exceptions were noted it was only when the stigmas of 

 the same or nearly related species were added that germination took place. From 



