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



343 



which remains vegetative. Gradually, as thetetrasporangium increases 

 in size, the last mentioned cell becomes slender and curved round 

 the tetrasporangia ; it gets a semilunar shape and its upper end 

 becomes connected with the cell above. In this way a reticular 

 tissue of vegetative cells is formed connecting the midrib with the 

 not fructiferous margi- 

 nal cells of the thallus. 



The antheridial 

 stands have previously 

 been found by Cramee. 

 I have come across a 

 few male plants in my 

 material. When Cra- 

 mer remarks that he 

 has foimd the anthe- 

 ridial stands upon 

 "kleinen Ceylonpflänz- 

 chen", my plants were 

 by no means especially 

 diminutive, on the con- 

 trary the thallus of the 

 male plant was even lar- 

 ger than that of the fem- 

 ale, at any case broad- 

 er. In the male plant 

 the breadth of the thal- 

 kis was two mm, in the 

 female only about 1^ 

 mm. 



The antheridial 

 stands (Fig. 339) occur 

 in the upper parts of the 



thallus as large coverings upon both sides of the thallus leaving the 

 midrib free and mostly, too, a narrow belt of vegetative cells along 

 the edge of the thallus. The cell-division in the male plant takes place 

 in nearly the same way as that in the vegetative one, only the cells 

 forming the tissue being smaller. From the surface of these cells 

 about 2 — 4 small cells originate from which the spermatia are cut off. 



As to the cystocarps I have only found a few. As described by 



Fig. 33i'. Caloglossa Leprieurii (Mont.) J. Ag. 



Part of a male plant with antheridial stands. 



(About 30:1). 



