16 



Dansk Botanisk Arkiv, Bd. 2. Nr. 2. 



Only plurilocular sporangia were met with; their shape was 

 rather characteristic being oval-rectangular with roundish angles 

 (Fig. 9 a and b) ; a few longer, clavate sporangia with undu- 

 lated walls were also found (Fig. 9 c, d). The loculi are large, 

 about 8 p high and 10 p broad. 



The oval sporangia were about 22 p broad and 33 p long ; 

 the longer, clavate ones up to 64 p long and 27 p broad. 



The sporangia are mostly sessile, rarely borne on a short 

 stalk (Fig. 9 e). 



Fig. 9. Ectocarpus rhodochortonoides nov. spec. 

 a, part of a plant with plurilocular sporangia and a rhizoid. b, a plurilocular 

 sporangium and cells with chromatophores. c, a terminal plurilocular spo- 

 rangium, d, a clavate plurilocular sporangium, e, a stalked plurilocular 

 sporangium, f, base of a plant, (a, about 90:1; b—f, about 200:1). 



In the shape of the plurilocular sporangia with their large 

 loculi our plant strongly reminds one of Ectocarpus breviarticulatus 

 but in this species the sporangia are placed at right angles to 

 the filaments while these are here curved upwards. In addition to 

 this there is much difference in the vegetative parts of the plants. 



This species shows also some likeness to Ectocarpus varia- 

 bilis of M lle Vickers (Phycologia Barbadensis, Part II, pi. 31); 

 but this form differs from mine in its much shorter cells which 

 seem to be of the same length in the whole plant. Further the 

 shape of the plurilocular sporangia is also different. 



The few specimens found were collected in exposed places in 

 the littoral region. 



St. Croix: Northside, Cane Bay. 



