Champia par villa, Haw. from the Carpospore . 341 
two to four segments. This division of the outer cells of the 
segments breaks up the files of cells which radiate from the 
group of initial cells at the apex of the frond. The files of 
cells are not distinguishable after the division of the segments. 
The division of these cortical cells tends to lengthen the frond. 
As the frond thus grows in length, the cells which were cut off 
on the inside, when the segments divided in the plane parallel 
to the surface of the frond, lengthen into internal filaments or 
hyphae. The inner cells lengthen to keep pace with the 
growth of the frond. Every segment adds a cell to a hypha 
when it divides into the inner and outer cell. The frond 
increases in length by the division of the outer cells, and the 
inner cells lengthen as the frond grows. These inner cells 
form the long hyphae which traverse the length of the hollow 
frond on the inside. The hyphae begin near the apex of the 
frond, under the files of segments, which are cut off from the 
initial cells. Of course there are as many hyphae as there are 
initial cells. 
The cells of the hyphae are often attached to the inside of 
the frond by one or more small cells, and usually have upon 
them, on the side nearest the axis of the frond, one large pear- 
shaped cell, the bulb-cell. The bulb-cells develop when very 
near the summit of the frond, and when several of them upon 
different hyphae meet and touch, they become fastened to- 
gether, and by farther growth form the transverse diaphragms, 
so characteristic of the species. 
Some of the botanists who have published papers on the 
structure of this alga and allied species have held views as to 
their manner of growth which differ widely from the view of 
Debray and Bigelow. Carl Nageli 1 believed that Lomentaria 
kaliformis had an apical cell at the tip of each branch, and 
that this divided by oblique partitions to form the frond. 
Dr. G. Berthold 2 described and gave a diagram of the tip 
of Champia parvula. He pointed out that there was a group 
1 Carl Nageli, Die neuern Algensysteme, p. 246, 1847. 
2 Dr. G. Berthold, Beitrage zur Morphologie und Physiol ogie der Meeresalgen. 
jahrbucher f. wiss Botanik, Bd. xiii. p. 686, 1882. 
