1898 | CURRENT LITERATURE 453 
M. Cu. DASSONVILLE has made an elaborate study of the effect of min- 
eral salts upon plant structure.” A great number of experiments were made, 
in which direct control was had by germinating in solutions, while supple- 
mentary evidence was gained by germination in soil to which either solutions 
of asingle salt of graded strengths were presented, or complex solutions 
accompanied by check experiments in which the salt under study was omit- 
ted from the complex solution presented. Check experiments in distilled 
water accompanied those in which germination was effected in a liquid solu- 
tion. Certain mineral solutions induced more vigorous growth of both vege- 
tative and floral parts, but a period of life no longer than in aqua pura. 
Dassonville presents also the surprising results that cutinization, sclerification, 
and lignification are much more accentuated in young plants in distilled water 
than those of the same age in mineral solutions. The observations are not 
directed so much to general effects as to the most intimate histological alter- 
ations. One comprehends that the work must be most extensive to present 
reliable results. 
The effect of particular salts may be summarized as follows : magnesium 
sulfate retards normal development only at first, later becoming indispensable 
or it. In the castor-oil plant the retarding effect is chiefly upon the terminal 
root, which is atrophied. Later adventitious roots develop, the more the 
stronger the solution. In hemp there is no adventitious development, but 
the secondary wood is stimulated and the primary vessels retarded. 
Potassium phosphate is necessary at all stages. Its absence insured a 
characteristic abnormal development of the roots. Its presence stimulates 
the sclerification of the pericycle. 
Potassium silicate deepens the green 
ture and lignifies the peripheral cells of the root tip. 
The effect of nitrates varies in different plants, and with the strength of 
the solution and the stage of development. No attempt was imade t0 ane 
late a general law from the confusing results of the seven types - i 
However, the acetates of ammonia and potassium seem best for hemp an 
buckwheat, while sodium acetate is deleterious. No matter what the base, 
the acetates call forth a special tint in the leaves, which the author, attributes 
especially to acetic acid. 
Potassium stimulates growth, but retards t 
chyma, and may thus increase the liability of 
Sodium is less favorable to growth, but hastens 
preventing “lodging.” 
Calcium chloride and magnesium seem 
buckwheat, and the decreasing order of uti 
acetic, phosphoric, hydrochloric. 
of the leaves and affects their struc- 
he differentiation of scleren- 
«“Jodging ” in the Graminee. 
lignification of the stem-base, 
equally beneficent to hemp and 
lity of acids for these types 1S 
étaux. Revue 
27 Influence des sels minéraux sur la forme et la structure des vég' 
générale de Botanique 10:15 sqq- 1898. 
