PHAOPHYCE A 63 
and are set free by the dissolution of the cell-walls. 
The sporangia occur in clusters in Padina and 
Taonia, and in scattered fashion in Dictyota. The 
prevailing number of spores is four, but frequently 
only two, or rarely one. The division into four is 
either simultaneous, when the resulting arrangement 
is that of a tetrad, or by two successive bipartitions, 
when the four spores lie in one plane. The spores 
escape by an apical opening of the sporangial wall, 
are motionless, and at first without a membrane. 
They soon, however, secrete a cell-wall and germinate. 
The process of germination, so far as it has been 
observed, is the same for spores and oospores, but 
the product of germination is either directly (Dictyota 
and Zonaria) a small plantlet of the parent form, or 
(Padina, Taonia, and Dictyopteris) a protonema-like 
body from the superficial cells of which one or more 
shoots arise in the form of the parent plant. 
None of the Phceophycee have caused greater 
diversity of opinion as to their relationship than the 
Dictyotacee. Some authors have gone so far as to 
place them with the Mloridee or in a position apart 
from the Pheophycee but pointing towards the 
Floridew, and this indeed appears to be-the favourite 
view of their character, especially with those who 
demand a link between Phawophycew and Floridec 
(though such a link might perhaps better be sought 
lower in the scale than the WDictyotacew). This 
opinion is based on the unciliated character of all 
the reproductive bodies, the resemblance of the 
motionless antherozoids to the pollinoids of Moridce, 
and the division into four of the spores constitutmg 
