F. Børgesen : Rhodophyceæ of the Danish W. Indies. 305 



As far as I know the tetrasporangia are up to this date the 

 only known organs of fructification of this plant. The discovering 

 of a small piece of a male plant and of a female one, was there- 

 fore of much interest. Neither the antheridia nor the cystocarps 

 show any more essential peculiarities; both kinds of fructiferous 

 organs are very hke those, e. g. found in Polysiphonia. 



As, in the case of the stichidia, the antheridial stands (Fig. 308) 

 are found in the tricho- 

 blasts and originate from 

 the first side-branch of 

 these.But while the whole 

 side-branch is employed 

 in the development of 

 the stichidium, this nor- 

 mally having no branch- 

 lets, this side-branch in 

 the male plant has one 

 to three branchlets be- 

 sides the terminally pla- 

 ced antheridial stand. 

 The antheridial stands 



are cylindrical to 

 spindle-shaped, with an 

 obtuse apex. At their 

 base they have a stalk 

 composed mostly of 

 three short cells and, at 

 their summit, two small 

 sterile cells. 



The development of 

 the antheridial stands 

 takes place in the follow- 

 ing manner: the branch at first is divided by transverse walls 

 in a number of short cells above each other (Fig. 309 a) where- 

 upon these again are divided: firstly by longitudinal walls (Fig. 

 o09 6), later by walls in various directions into a great number of 

 small roundish-polygonal cells at the pheriphery. From these the 

 antheridia are formed. 



The procarps originate from the second segment of the tricho- 

 blast (Fig. 310). This becomes polysiphonous, consisting of the 

 central cell and the five pericentral ones as always in the case of 



Dansk Botanisk Arkiv. Bd. 3. Nr. 1 (1919). 20 



Fig. 308. Lophocladia Irichoclados (Mert., C. Ag.). 

 Schmitz. Part of a filament with triclioblasts, 

 two of which bearing antheridial stands. 

 (About 100 : 1). 



