198 



broader stalk-cell. In some specimens from the Little Belt (Middelfarl) the paraphyses 

 were but few in number, in some cases almost wanting; the plant had then a cer- 

 tain resemblance with Rhododiscus piilcherrimus. 



The sporangia are first divided by a transverse wall; the vertical walls occur 

 at a later moment, for which reason sori containing only bipartite and undivided 

 sporangia are not infrequently met with (comp. Kucki ck 1. c. p. 7 and Batters 1. c. 

 pi. XI fig. la). The ripe sporangia are usually 24—33/^ long, 16—20(24) f2 broad. 



oa 







B 



,aCX3 



Fig. 118. 



lUioilodermis cleijans. A, marginal part of frond seen from aljove. B, basal layer of fructifying frond seen from 

 below. C, vertical section of fertile part of frond with parapliyses, a bipartite s|)orangium and a hyaline hair. D, 

 vertical section of frond with sorus : sporangia bipartite. E. almost glol)nlar ripe sporangium from Hornen:es. 

 F, ripe sporangium. G, regeneration of sjjorangium. 385:1. 



The greatest sporangium was found in a specimen from Refsnses; it measured 33/^ 

 in length and 24 /i in breadth. In the southernmost place in the Danish waters 

 (at Hornenajs in the Little Belt) I found almost globular sporangia, 20—21 r/ long, 18/^ 

 broad (fig. 118 E). After evacuation a new sporangium may be produced from the 

 stalk-cell within the empty sporangium wall (fig. 118 G). 



Sexual organs were not met with. Antheridia are only known in specimens 

 from North-East Greenland (K. Rosenvinge 1910). 



As to the time of fructification only incomplete information can be given. In 

 winter (October to February) the species has not been met with, but il must be 

 supposed from observations from the coasts of England and of Greenland, that it 

 will be found fructifying in winter with us, and this supposition is in accordance 



