28 . BOTANICAL GAZETTE ~ (jury | 
Corn roots grown in garden soil kept moist were found well : 
covered with hair after seven days. Other pots were submerged | 
in water for eight days. The uninjured primary roots showed long | 
bare spaces and the laterals were nearly or entirely bare. One 7 
plant was allowed to dry out and the roots again became haired. 3 
‘Wheat was grown in garden soil in pots, one of which was placed — 
‘in water and the other watered a little every day. After a week’s4 
growth, the plants were found to have abundant hair on the roots 
passing through the pots into water, only zones of papillae on the 
roots in saturated soil, but good hairs on those in-the dry pot. The 1 
‘zones May correspond to the drier conditions when the water fell — 
below the bottom of the pot. In a control experiment’ precautions | | 
“were taken to obviate the possible effects of a lack of mineral salts 
in the water on account of the absorptive action of the soil particles. 
It seems’ therefore that something besides lack of nutrient salts 
(probably lack of oxygen) must’in this case be the important facto 
Le. Osmotic solutions. 
In connection with the experiments with osmotic solutions, cleaned 
sand was saturated with solutions of lactose, saccharose, and glucos 
of a concentration which allowed the zone of hairs to form. I 
lactose and glucose the hairs were much reduced and their presenc 
in saccharose was extremely doubtful. 
The effect of solutions upon the growth of plants and plant organs q 
has been extensively investigated, but many of the results reported _ 
are of little use on account of a failure on the part of the investigators | q 
to distinguish the physical effect due to the osmotic action of the — 
solution, and the chemical effect of the ions (LIVINGSTON 44, 
124-7). Many authors (Not. 57a, GERNECK 18, ef al.) thin 
the characteristics of water roots to be due to the lack of nitrate 
in the culture. The results of GERNECK and Krassnow (36a), 
connection with the form and structure of water roots. Mere specu 
lation on the subject, however, is of little value ; careful physical 
