BOTANY. 1009 



pis. 10, figs. 5; abs. Bot. Centbl., Beihefte, 8 (1898), No. 4-5, p. 291; Gompt. 

 Bend. Acad. Sci. Paris, 126 (1898), No. 11, pp. 856-858; Bot. Ztg., :>. Abt., 

 57 (1899), No. 4, pp. 54, 55). — The influence of salts on the growth of 

 plants was investigated in a number of ways. Plants were grown in 

 distilled water and in Ivnop's solution (E. S. P., S, p. 744), and the 

 external and internal characteristics of each plant compared. In a 

 second series of experiments the effect of single salts was studied in 

 the same way, comparisons being made with plants grown in distilled 

 water and in Knop's solution. The effect of the absence of different 

 sails from the nutrient was also noted. The plants upon which most 

 of the experiments were conducted were seedling lupines, beans, rye, 

 oats, wheat, maize, flax, gourds, hemp, morning glory, castor bean, sun- 

 flower, mustard, buckwheat, tomato, and young plants of the potato. 

 For the most part, plants in the Knop solution grew well and flowered, 

 while those grown in distilled water were much smaller and did not 

 flower. The plants in distilled water remained alive as long as those 

 grown in nutrient solutions, and in some cases longer, and the small 

 amount of tissue developed by them was strikingly unlike the same 

 tissues in the other plants in that it was differentiated to a greater 

 degree. Plants in Knop's solutioo were larger and more vigorous, but 

 there was little differentiation of tissues. There was a lack in the 

 development of cuticular, sceleriform, and ligneous tissues when the 

 plant was highly nourished. 



. The difference in growth in distilled water and Knop solution of a 

 number of plants may be shown. The roots of bean plants grown in 

 the nutrient solution were less lignified, and there was a great increase 

 in vascular tissues as compared with plants grown in distilled water. 

 In the steins the vascular bundles were more numerous. The experi- 

 ments with oats were similar in their results. The oat leaves in the 

 nutrient solution possessed a greater number of nerves and a greater 

 development of mesophyll. The maize plants grown in distilled water 

 had no root hairs, while those in the Knop solution were abundantly 

 supplied with them, the air spaces were increased, and the vascular 

 bundles were augmented. Similar results were secured for most of the 

 other plauts with which the author experimented. In all there was a 

 marked absence of liguification when the plants were grown in nutrient 

 solutions. 



In the second part of the paper, in which the action of different salts 

 on the growth of plants is reported, it is stated that magnesium sul- 

 phate retards growth at first but later- seems essential to the develop- 

 ment of lupines, castor beans, and hemp. The retarding effect seems 

 to be principally shown on the roots, the main root of the castor bean 

 being atrophied. Potassium phosphate was found indispensable to the 

 growth of lupines, castor beans, rye, wheat, oats, gourds, and pine. 

 In wheat and oats it favored root growth in proportion to the quantity 

 present. Large amounts tend to prevent lodging in wheat and oats 



