442 



Further upon an old Dasya a tuft of a somewhat more robust 

 form was found (Fig. 415 e). 



The base of this plant was very like the Fig. 2A of SAUVA- 

 GEAU, 1. c., p. 31. The cells in the filament are about 8 10 ja thick. 



Hairs occur rather abundantly; they have a growing zone 

 at their base with a slightly developed sheath and are about 

 7 8 ;a thick. The erect assimilating filaments consist of about 

 4 cells; their diameter reaches a length of about 11 jn. Of pluri- 

 locular sporangia only a few unripe have been found. This plant 

 was dredged in about ten fathoms of water in the sound between 

 St. Thomas and St. Jan: off Cruz Bay. 



Geogr. Distrib.: The European and American shores of the Atlantic 

 Ocean, Mediterranean Sea. 



17. Ralfsia expansa J. Ag. 



18. Lithodernia spec. 



19. Aglaozonia Canariensis Sauvag. 



20. Sphacelaria tribuloides Menegh. 



21. furcigera Kiitz. 



22. Zonaria variegata (Lamx.) Mert. 



23. lobata Ag. 



24. Padina Sanctse Crucis B0rgs. 



25. gymnospora (Kiitz.) Vickers. 



26. Howeana nov. nom. 



Syn.: Padina variegata Hauck et auctores. HAUCK, F., Ueber einige 

 von I. M. HILDEBRANDT im Rothen Meere und Indischen Ocean gesammelte 

 Algen (Hedwigia, vol. 26, 1887, p. 41). VICKERS, A., Phycologia Barbadensis. 

 part II, pi. VIII. BORGESEN, F., The marine Algae of the Danish West Indies, 

 vol. I, p. 205. COLLINS. FR. S. and HERVEY, A. B., The Algse of Bermuda, 

 v. 87. 



Zonaria variegata Kiitz., Tab. Phyc., vol. IX, pi. 73, fig. 2. 



In a review of the parts of my paper dealing with the green 

 and brown alga? Dr. HowE 1 ) points out that when both Zonaria 

 variegata and Padina variegata are derived from LAMOUROUX'S 

 Dictyota variegata this practice cannot be kept up according to 

 the rules of nomenclature. 



Dr. HOWE writes: This practice, which did not originate 

 with BORGESEN, seems to rest upon the assumption that the 

 original Dictyota variegata of LAMOUROUX was a mixture of two 



l ) In Torreya, vol. 15, 1915, p. 46. 



