sat : :* - : 
ce Shecial Morphology and Classification. — 295. 
bodies. A vegetative mode of reproduction sometimes 
takes place by means of Jy/bils, which become detached. 
The ‘ punctum vegetationis,’ which is in the centre of the 
terminal bud, consists of two cells lying one above another ; 
while beneath the lower of these is another cell which 
divides longitudinally, and developes into the cellular trans- 
verse partition or node. Below this again is a single elon- 
gated internodal cell, and beneath this again a rudimentary 
node, and so on. ‘The internodal cells increase in size, but: . 
never divide. ‘The leaves or lateral branches, on the other | 
hand, are developed from outgrowths of some of the peri- 
pheral cells of the node. The cortical layer which surrounds 
each internode is developed, not from the internodal cell, 
but by continual growth and division of the peripheral 
nodal cells, which from the first overlap the internode, and 
gradually assume a spiral arrangement. The cells of Chara: 
always contain’ a nucleus, and afford a remarkably good 
illustration of the phenomena of rotation (see p. 10). This 
movement is exhibited especially in the inner layer of 
protoplasm next the central vacuole, the nucleus being 
carried round in the stream ; while the outermost layer 
which includes the chloropayll-grains is quite motionless. 
The eight cortical cells of which the wall of the 
antheridium or globule consists, are sometimes called 
siields ; the four nearer the base are four-sided, the four 
nearer the apex three-sided. From the middle of the inner 
face of each shield, a cylindrical cell, termed a manubrium, 
projects inwards, nearly to the centre of the hollow globule; 
and at the extremity of each manubrium is a roundish 
hyaline cell, the “ead or capitulum. ‘The shields, manubria, 
and capitula form therefore together twenty-four cells, 
which, together with the pedicel-cell of the globule, consti-_ 
tute its framework. Each capitulum bears six smaller cells, 
secondary heads or capitula; and from each of these grow 
four long whip-shaped filaments, the number of which there- 
fore 1s about 200. Each of these 200 filaments divides 
