200 Phillips . — On the Development of the 
and Chondria may not now justify their inclusion in one 
genus, after the plan of earlier authors, it would certainly 
seem to be a reason for not separating them among dif- 
ferent tribes as Schmitz does, much less among different 
families as Agardh does. 
POLYSIPHONIA THUYOIDES, Harv. 
This plant belongs to the strongly corticated group of the 
genus Polysiphonia , and is the Rhytiphlaea thuyoides of the 
Phycologia Britannica (4 b). I have found the procarps to 
correspond closely with those of other Polysiphonia , excepting 
that at the period of the fertilization of the trichogyne 
a superior cell, undoubtedly an auxiliary cell, is already 
separated from the pericentral cell. I have hitherto assumed 
that this separation of a superior cell was a consequence of 
fertilization of the trichogyne. It would, however, appear to 
be cut off in this case at, or even before, that period ; usually it 
appears immediately after, and in Dasya long after, that period. 
Summary. 
I propose now to briefly summarize the results obtained 
from the examination of the eight species of Rhodomelaceae, 
the cystocarps of which I have studied in some detail. The 
description of the cystocarps of four of these species is 
contained in a former paper in the Annals (1). The eight 
species represent five genera, and four of the groups of genera 
(or tribes) as arranged by Schmitz (3 b). 
Tribe Rhodomeleae 
,, Laurencieae 
„ Polysiphonieae 
Dasyeae 
Rhodomela subfusca. 
Laurencia pinnatifida . 
P olysiphonia nigrescens , fastigiata , 
■violacea, and thuyoides . 
Chondria tenuissima. 
Dasya coccinea. 
In entering upon a comparison it will be found convenient 
to take the structures in the following order : the procarp in 
