Halket .— The Effect of Salt on the Growth of Salicornia. 145 
pans. The pans were divided into four sets of six, two (a and b) with 
seedlings of Salicornia ramosissima , and two (c and D) with seedlings of 
Suaeda maritima. In each lot each pan was treated differently, and was 
watered with a solution containing one of the following quantities of 
Tidman’s sea salt, o %, 1 %, 2 %, 3 %, 4%, or 5 %. Solutions of Tidman’s sea 
salt were used so that the plants should be exposed to an influence 
resembling, as far as possible, that of sea water. 
The sods were cut near the end of April when the seedlings were very 
young. These were apparently all at the same stage of development, their 
cotyledons were expanded, but no epicotyls were visible above the level of 
the cotyledons. The experiments were begun on April 28 and were con¬ 
tinued till June 25. The plants were exposed to the different degrees of 
salinity by immersing the pans in the various solutions for a period of two 
hours or longer every seven days or so. If the soil became dry between 
the immersions, the pans were watered with equal volumes of the appropriate 
solutions. 
It was soon evident that the rate of growth of Salicornia and Suaeda 
differed in the various pans, and this difference became increasingly evident 
as the treatment was continued. Certain plants, five in number, were 
chosen in each pan, and the rate of growth of their epicotyls noted by 
measurements taken at intervals. But, as there was found to be considerable 
variation in the height of the plants in the same pan, the curves of growth 
so obtained are not of sufficient value to warrant their reproduction here. 
The sods were untouched before the treatment began, the seedlings were 
allowed to remain as the seeds had fallen and germinated, so that they were 
not at all evenly distributed. It was thought therefore that the variation 
in the height of the individual plants in the same pan was due to the com¬ 
petition of the plants with one another, and with the Glyceria which was 
also present. In spite of this variation in size of some of the plants, the 
effect of the various degrees of salinity on the growth of the plants as 
a whole was very evident, and is best shown by a comparison of the average 
height obtained by the plants in the different pans. On June 1, nearly five 
weeks after the treatment was begun, the length of the epicotyl of each 
plant was measured and the average for each pan calculated. The figures 
obtained are given in the table below: 
Table I. 
Average height of plants in millimetres. 
Tidmaris 
sea salt. 
Salicornia 
ramosissima. 
Suaeda maritima. 
% 
A 
B 
C 
D 
0 
8*2 
9*7 
n*7 
io *8 
1 
n*9 
12*7 
12*4 
9*9 
2 
5*5 
7*3 
10*0 
8 *o 
3 
4*4 
3*7 
8 *o 
6-2 
4 
2-3 
3*o 
4 *i 
2-3 
5 
2-3 
3*2 
L 
4*7 
2‘6 
