260 



Dansk Botanisk Arkiv, Bd. 3. Nr. 1. 



Fig. 253. Acanthophora spicifera (Vahl) Borgs 



Part of a plant with antheridial stands. 



(About 10:1). 



filaments, the branches issuing from 

 no spiny hranchlets, as is the rule 

 Falkenberg, Rhodomelaceen, p. 226). 

 stop their growth, becoming short 

 branchlets. But now and then a single 

 one of these branches grows out to 

 filaments with continuous growth, like 

 the main filaments. The branches and 

 branchlets are arranged spirally with 

 a ^/4 divergency upon the filaments. 

 The spines are found mostly in the 

 upper end of the branchlets. 



The branches issue from the ba- 

 sal cell of the trichoblast, just as in 

 the case of Acanthophora orientalis, 

 as pointed out by Falkenberg, 1. c. 

 p. 231. In fig. 255 the summit of a 

 plant is shown in which a great deal 

 of the trichoblasts covering the sum- 

 mit are taken ofY. From the basal 

 cells of the trichoblasts we see a 

 young branch issuing, the beginning 

 of the branchlets or branches. It is 



As pointed out in my 

 paper quoted above, this 

 species ought to have 

 Vahl's old name, being 

 originally described by 

 him from specimens from 

 St. Croix. For further de- 

 tails as to this matter I 

 refer to my paper. 



Acanthophora spicifera 

 is fastened to the sub- 

 stratum by means of a lar- 

 ge, irregularly lobed disc, 

 from which often many 

 erect filaments issue. 



It belongs to the 



group of species which 



lack spines upon the main 



these having at their base 



in the other group (comp. 



Most of the branches soon 



Fig. 254. Acanthora spicifera 

 (Vahli Børgs. Partof aplantwith 

 tetrasporangia. (About 10:1). 



