Postelstia 
~I 
On 
of the water. The depth at which it is anchored 
wanes irom.1-2 meters as a general rule: It 
seems to prefer a bottom of fine silt or mud where 
the proportion of sand is not considerable. 
Under these limiting conditions there are only a 
few places along the shore of the lake where it 
has been able to gain sufficient foothold to build 
up a characteristic society. 
Other aquatic representatives occur but spar- 
ingly. At the time of the year when the place 
was visited only two other species were observed 
growing in the lake. These were Callitriche 
palustris and Sparganium minimum. ‘They are 
found at intervals along shore, generally in shal- 
low water, and do not seem to show any strong 
preference as to the nature of the bottom.- No- 
where do they develop in any considerable 
quantity and must be regarded as outposts of 
the general lake flora. 
Special adaptations—In forests of such high 
latitudes as that of Vancouver Island epiphy- 
tism is generally confined to the lower plants 
like lichens, liverworts and mosses. The last 
two groups are particularly abundant in the 
