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



401 



Fig. 385. 

 Chrysymenia 

 pyriformis 

 Børgs. 

 A little magni- 

 fied (about 

 1V4:1). 



this cortical layer leaves a space free over the 

 middle of the large cells, while in older vesicles 

 the cortical cells very often cover them completely. 

 The wall of the vesicles is about 90 // thick. The 

 cavity in the interior is filled with mucilage. 



A transverse section of the solid stem (Fig. 

 387) shows great likeness to that of Chrysymenia 

 microphysa Hauck as drawn by Kuckuck (1. c, 

 p. 210). The cells are largest in the middle, de- 

 creasing gradually towards the periphery. 



On the inner side of the large cells, facing the 

 cavity in the interior of the vesicles, we find 

 here and there groups of gland-cells (Fig. 386 A, C). 

 These are pear-shaped, occurring from two to about 

 eight together in a bunch. Sometimes, too, a 

 solitary gland-cell is present. The cells bearing the 

 gland-cells are mostly smaller than the surround- 

 ing cells. 



Only sterile plants have been gathered. 

 Compared with Chrysymenia microphysa Hauck — of which 

 we have a detailed description since I described this species 

 by the late Prof. Kuckuck — our plant differs essentially 

 by its larger size, 

 larger and different- 

 ly shaped vesicles of 

 which the Mediter- 

 ranean plant most- 

 ly bears but a single 

 terminal one upon 

 each stem. Further- 

 more, glands are 

 not found intheMe- 

 . diterranean plant. 

 Of the hitherto 

 known Chrysyme- 

 nia-species in the 

 West Indian waters 

 this plant comes, 

 as I have already 



Dansk Botanisk Arkiv, Bd. 3, Nr. 1. (1920) 



Fig. 386. Chrysymenia pyriformis Borgs. 

 A, transverse section of the wall, in the middle a 

 cell with glands (70:1). B, part of the wall seen 

 from the surface (70:1). C, large ceils of the wall 

 facing the cavity, one of the cells with glands 



(70:1). 



26 



