166 Mottier.—Nticlear and Cell Division 
details of both nuclear figure and remaining cytoplasm are 
less sharply defined. The staining process was the same 
as that used by myself in cytological studies on the higher 
plants (Mottier, ’ 97 , ’ 98 ). 
The Cytoplasm. 
The following remarks pertain to the tetraspore mother-cell, 
unless otherwise stated. 
The cytoplasm, especially during the preparation for the 
process of nuclear division, reveals two well-defined and 
sharply differentiated portions, a fibrillar portion, the kino- 
plasm, which is always associated with the nucleus and which 
plays the most important role in the karyokinetic process, and 
the remaining alveolar portion or trophoplasm of Strasburger. 
The alveoli (Waben of German authors) are relatively large 
and generally uniform in size (Plate XI, Figs. 2, 8); their 
walls or lamellae are generally smooth and of a uniform 
thickness. Upon the lamellae and in the angles of their 
meshes are often present numerous small granules which 
impart the granular appearance to the alveolar structure. 
Among the larger alveoli there are also present, especially 
in the vicinity of the nucleus, smaller meshes of granular 
plasma. This is partly fibrillar and partly alveolar. 
In neither the reproductive nor the vegetative cells of 
Dictyota do we have a differentiation of the alveolar plasm 
into two sharply defined zones as in Stypocaulon (Swingle, ’ 97 , 
Figs, i and 4), namely a region of rather uniform and small 
meshes surrounding the nucleus and one of much larger 
meshes occupying the remaining part of the cell. 
Regarding the terms kinoplasm and trophoplasm , Stras¬ 
burger (’ 98 ), in a critical and exhaustive discussion of the 
cell-wall and its origin, proposes for these physiological terms 
others of morphological significance, namely, filar plasma 
and alveolar plasma. He does not intend, it seems, that the 
latter terms should entirely replace the former, but that they 
be used in connexion with them (p. 517). 
