374 Dansk Botanisk Arkiv, Bd. 3. Nr. 1. 



St. Croix: Christianssted's harbour and lagoon; Lt. Princess, Green 



Cay; Longford. 



Geogr. Distrib.: Warmer Atlantic coast of Europe, Morocco, Medi- 

 terranean Sea, West Indies, Cape, The Philippine Islands etc. 



2. Gracilaria ferox J. Ag. 



Agardh, J., Spec. Alg., vol. IL p. 592: Epicr., p. 414. 



A few not very typical specimens may, I think, be referred 

 to this species. The ramification and whole hahit of this plant 

 shows some likeness to Gr. cervicornis, but this last species has 

 a compressed thallus. The branches are subdichotomoiisly rami- 

 fied, the ramuli short with acute apex, in the upper part of the 

 thallus often aculeate. 



From a transverse section of the thallus it appears that the 

 cells in the middle are large, growing smaller outwards. They 

 have thin walls. The cortical layer is thin, one to two layers thick. 



The plant was once gathered on rocks near the shore in a 

 rather exposed place, and once in the open sea at a depth of about 

 5 fathoms. According to J. Agardh it has previously been found 

 at St. Croix, and in the Botanical Museum, Copenhagen, a speci- 

 men collected at this island by Ørsted, is present. 

 St. Croix: White Bay, off Frederikssted. 



Geogr. Distrib.: West Indies, Pernambucco. 



3. Gracilaria compressa (Ag.) Grev. 



Greville, R. K., Algæ Brit., 1830, p. 125. Harvey, Phycol. Brit., 

 pi. 205. J. Agardh, Spec. Alg., vol. II, p. 593; Epicr., p. 417. 



Sphærococcus compressus Ag., Spec. Alg., p. 308; System., p. 233. Küt- 

 ziNG, Fr., Spec. Alg., p. 774; Tab. Phycol., vol. 18, pi. 78. 



Comp, for more synonyms De-Toni, Sylloge Alg., vol. IV, Sect II, 

 p. 438. 



Only a few not very typical specimens may, I think, be re- 

 ferred to this species. Compared with Gracilaria confervoides they 

 especially differ on account of their somewhat thicker thallus 

 and of the smaller cells in the interior of the filaments, their dia- 

 meter reaching only a length of about 300 H. The cells have thin 

 walls. The cortical layer is thin, composed only of one or two layers 

 of cells. The thallus is of a soft consistence and collapses in 

 drying. 



According to J. Agardh (1. c.) this species has been found 



