(246) 
nates not as a direct growth from the spore, but as a bud from the 
pro-embryo. The remaining cells of the upper node give rise 
merely to rudimentary leaves. 
The development of new cells from the growing point proceeds 
uniformly throughout the entire plant, from the first division in the 
first formed pro-embryonic superficial node-cell until the cessation 
of growth, which is more or less indefinite, especially in perennial 
species. 
The growing point or apical cell first divides transversely into two, 
a new apical cell, and what is known as the segment-cell, the former 
enlarging somewhat and again dividing similarly an indefinite num- 
ber of times. 
The segment-cells thus formed have a uniform history. Each 
divides by a transverse wall into two, and the lower of these be- 
comes elongated, its ultimate length being most often from 2 to 10 
cm., but it never undergoes further division. Such cells are the in- 
ternodes. The node or upper division of the segment-cell elongates 
very slightly, but is capable of division and from it all the remaining 
parts are produced. It first divides into two, then each of these sep- 
arates off a superficial cell, which divides into a variable number of 
cells. These latter, following the same plan of division as the apical 
cell of the stem, proceed to form long slender organs, called leaves, 
which maintain the same succession of nodes and internodes, but 
their number is usually fairly definite in any given species. In the 
genus Chera,a cell segmented off from the inner side of that node- 
cell which forms the first of these leaves, often gives rise to a branch, 
which exactly repeats the history of the stem. Branches may be 
formed at any node, and may even in their turn give rise to branches, 
in which case the plants may appear bushy in spite of the slender- 
ness of their stems. This appearance is also, and much more fre- 
quently, due to luxuriant growth of the leaves or leaflets. From the 
leaf-nodes leaflets are produced, but these do not divide and are 
never corticated. On the anterior side of the leaf-nodes, too, the 
sexual organs, antheridia and odgonia, are borne, and the leaflets 
surrounding these, known as bracts when the Characeae were con- 
sidered to be flowering plants, are perhaps better called (though 
this name too is unsatisfactory) bracteoles. They are usually larger 
than the leaflets at the sterile nodes. aking any individual node 
into consideration, leaflets or bracteoles may be similar or very dif- 
ferent; when the latter is the case, the posterior are nearly always 
the smaller, often greatly reduced, or even wanting. 
