1] MICROSCOPIC PLANTS. 7 
we shall come across a few instances of movement in 
the higher plants in the present volume. 
Whilst we have been talking another specimen. has 
come into the field of vision; and if you are not 
quick, you will lose a sight of it, It is 
the Pandorina morum, and it consists of 
a round cell containing a large number 
of smaller round cells or spores, each 
spore provided with two cilia, which pro- 
trude through the wall of the larger con- 
taining cell. But I have here, on another slide, a 
more remarkable and most beautiful form of similar 
construction. This is the Volvox globator, a species 
that once puzzled scientific men considerably, to 
assign the department of nature to which it be- 
longed. Some considered it was an animalcule, 
others thought it was a plant, but it has now been 
satisfactorily settled that it is a plant. It is a most 
beautiful object under our microscope, as it moves 
majestically across the field of vision, revolving con- 
tinually by means of the mul- 
titude of cilia with which its 
surface is studded. These cilia 
are disposed in pairs, as will be 
seen on reference to the illus- 
tration, and each pair marks 
the presence of acell. These 
cells are united by very fine 
threads, and within the sphere 
thus formed the young Vol- 
voces revolve. Where found, they are usually in 
great profusion—in fact, the water in some ponds 
