F. Børgesen: Phæophyceæ of the Danish W. Indies. 11 



The branches are inserted in a right or somewhat acute angle 

 to the main filaments (Fig. 5) and they are most often curved 

 upwards (Fig. 6 a). 



Upon their upper side in the angle between the branch and 

 the mother-cell the sporangia are found. 



The plurilocular sporangia are oblong-ovoid to conical and 

 always sessile. Most often only a few, 1 — 3, sporangia occur in 

 each angle, the largest of these, as a rule, being nearest to the 

 main filaments (Fig. 6 a) ; but now and then a greater number 

 develop; though a case with as many sporangia as is found in 

 the fig. 5 (lowermost branch) is rare. More rarely plurilocular 

 sporangia also were met with upon the main filaments (Fig. 6 b). 

 The plurilocular sporangia are of rather variable size, the 

 smaller ones about 40 ^ long and 24^ broad while the larger 

 may reach a length of up to 110 ix and a breadth of about 40 fx. 

 The few unilocular sporangia found occur at the same place 

 as the plurilocular sporangia, namely in the axis between the 

 main filament and the branch (Fig. 6 d) ; they were nearly ovoid 

 in shape and always solitary. 



The chromatophores consist of small roundish discs, fairly 

 numerous in each cell (Fig. 6 /). 



It cannot be denied that this plant shows some likeness to 

 Ectocarpus Hincksiæ Harv. but on the other hand it differs so 

 much in several respects from Harvey's species that it cannot 

 be considered a form of this species. 



Thus the ramification is much more irregular than in Ecto- 

 carpus Hincksiæ with its usually regularly arranged, short, secund, 

 pectinated, ramuli. 



Furthermore the ramuli in the West Indian plant have 

 marked intercalary growth-points near their base and invariably 

 terminate with long, nearly colourless hairs, while in E. Hincksiæ 

 the cells of the ramuli are divided nearly everywhere l ) and are 

 short and all nearly the same size. Sauvageau however (1. c.) 

 mentions that occasionally some specimens are provided with 

 short hairs. In specimens from the Færoes I have found no 

 hairs. 



The plurilocular sporangia occur usually solitary or a few 

 (2—4) together in the axils of the ramuli in contradistinction to 

 the usually numerous seriated sporangia of Eet. Hincksiæ. 



And the elongated conical shape of the sporangia in the 



l ) Sauvageau, C, Observations relatives a la sexualité des Phéosporées, 

 Journal de Botanique, 1897, p. 66. 



