6 MICROSCOPIC PLANTS. [CHAP. 
—Conferve—one of the Oscillatoria. It is very simi- 
lar in appearance to Zygnema, but is much narrower, 
and the cells are very 
<s” short. Nowlookat them 
under the microscope; 
they are gently moving 
over each other in all 
directions. It is from 
this peculiarity—this oscz//ating motion—they derive 
their name. Mr. Berkeley says of this tribe of 
plants :— 
“Oscillatorie grow in various situations—in salt 
and fresh water, on damp ground, amongst grass on 
close-shaved lawns, like lichens on the trunks of 
trees, floating on the surface of lakes and seas, or 
suspended like a cloud, giving rise to variously 
coloured waters. One or two fine purple species 
form thick woolly fleeces in the hotter parts of India, 
while many inhabit hot springs.” 
You think it strange that these low forms of plant 
life should have the power of motion, but that is only 
because you have been in the habit of observing large 
trees and bushes which are fixed to the ground by 
strong branched roots. Yet even these have certain 
powers of movement—at any rate, during portions of 
their lives. Have you not observed how plants bend 
towards the light, and how some that in the morning 
inclined to the east, in the evening lean to the west? 
Then look at climbing plants, how they move round 
a stick or string. Mr. Darwin, the great naturalist, 
has written a book devoted entirely to the “ Move- 
ments and Habits of Climbing Plants,” and probably 
Fic. 3. 
