< 0LLIN8 \\i> lit l;\ El . 



of the opinion that there is no justification for keeping color forms 

 distinct taxonomically. Both color- occur in nature, both in dried 

 material; plants originally aeruginous may change to red, plants 

 originally red fade to pale green. We have no suggestion to mak< 

 to the causes detennining these changes, except the general principle 

 in regard to filamentous Nostocaceae, that red forms generally occur 

 where the plant is always under water, not left exposed at low tide. 



1. I.. M.MiPi.iA \ .1. (i. Agardh ex Gomont, 1893, p. 158, PI. III. 

 11. Not uncommon among other small algae; rarely pure. 



5. Lyngbya i.itka Gomont, L893, p. 161, 11. III. figs. 12 & L3. 

 Among various small algae, not found pure; bright red form on 

 Co<lin in, Harris I Jay. Dec., Ilervey. 



*(i. L. Lagerheimd Gomont, L893, p. L67, PL IV. 1 On 



decaying Sargassum, near Shelly Bay, April, Collins. 



Svmploca Kutzing. 



1. Cells 1-2 diam. long, aeniiiinous. 1. S. muscorum. 



1. Cells much shorter than their diam., violet. 2. B. violaeea. 



*1. S. m. - OBI m Gomont, 1S93, p. L30, II II, fig. 9. On rock by 

 roadside, Aug., Collins. 



2. S. vioi.A. \.\ Ilauckex Porti, L907, p. 311; Hauck, L885, p. 507, 

 fig. 224. On ground near margin of pool in woods by Walsingham, 

 April, Collins. This appears to have been overlooked by Gomont in 

 his monograph either as an accepted species or anion:: "species in- 

 quirendae" or "species excludendac" Ilauck's record is included 

 by Forti in the Sylloge, and by the international rules, which fix 

 GTomont's monograph as the point of departure for homeocysted 

 filamentous Nostoehineae, 1907 is the date of publication. The 

 Bermuda plant agrees with Ilauck's description and figure; the violet 

 color and short cells distinguish it from all other marine speci< 



PLECTONEMA Thuret. 



•P. Nobtocorum Bornet ex Gomont, 1893, p. L22, PI. I. fig. 11. 

 Common in gelatinous masses of algae of various kinds. 



PORPHYROSI PHON KtitZU 



*P. NoTARisn Kutzing ex Gomont, l^ ( .».'i, p. 69, PL XII. figs. 1-2. 

 On Junipertu bermudiana, Aug., Collin-. 



