THE ALGAE OF BERMUDA. 151 



3. D. CAEiBAEA (J. Ag.) Setchell, 1912, p. 241, PL XXVI; Calo- 

 siphonia caribaea J. G. Agardh, 1899, p. 84. Cooper's Island, Feb., 

 Farlow; washed ashore in abundance. This species and the pre- 

 ceding are very much alike in habit, and can be distinguished with 

 certainty only by microscopic examination of plants in fruit. 



These three species of Dudresnaya illustrate the possibilities of algae 

 collecting. D. hermudensis is known only from Bermuda, from the 

 material collected by Farlow on a single day in 1881 at Cooper's 

 Island, and from a single collecting at St. George's in 1916 by Hervey; 

 the Bermudian material of Z). caribaea was all collected on the same 

 day in 1881, and only one other station, Tortugas, Florida, is known; 

 Calosiphonia verticillifera was collected at the same day and place, 

 and is known elsewhere from the Tortugas station only. Material 

 of all three species was abimdant that day, but there is no record of 

 any one of the species since, except the single collecting of D. hermuden- 

 sis, though we have both been on the watch for them for the past five 

 years, and have made visits to Cooper's Island at the same time of 

 year as Farlow's collecting and at other times, to search for them. 

 On the other hand we have found D. crassa, not known until 1905, in 

 abundance at distant stations. 



Family NEMASTOMACEAE. 

 Calosiphonia Crouan. 



C. VERTICILLIFERA (J. Ag.) Setchell, 1912, p. 247, PI. XXVIII; 

 Helminthiopsis verticillifera J. G. Agardh, 1899, p. 98. Cooper's 

 Island, Feb., Farlow. As noted under Dudresnaya, this is one of the 

 three species of handsome red fleshy algae, found in abundance on the 

 same day in 1881, at Cooper's Island, and not observed since. In 

 habit it is^notunlik&JDudresnaya, but is distinguished on microscopic 

 examination by the shorter and stouter peripheral branches, forming 

 a definite cortical layer. 



Platoma Schmitz. 



P. CTCLOCOLPA (Mont.) Schmitz, 1889, p. 453; Halymenia cyclo- 

 colpa Montagne, 1840, p. 163; 1846, p. 116, PI. XI, fig. b; Nema- 

 stoma cervicomis J. G. Agardh, 1879, PI. IV, figs. 1-4. Cooper's 



