600 CLADOPHORACEAE. 



Filaments 10—28 fi in diameter ; cell walls mostly 



1-4 fjL thick. 

 In or near salt water ; cells mostly 1-2 times as 



long as broad ; chromatophore usually rather 



solid and uniform. 3. R. ripariuni implexum. 



In fresh water ; cells mostly 1—5 times as long 



as broad : chromatophore usually lacunose or 



resolved into discs, plates, or bands of protean 



forms. 4. R. hieroglyphicum. 



1. Rhizoclonium Hookeri Klitz. Sp. Alg. 383. 1849. 



High-littoral to low-water mark, often in Rhizophora association : — Bermuda 

 and Florida to South America. Type from Kerguelen Island. 



The West Indian plants currently referred to this species appear to be coarser, 

 longer-celled, and thicker-walled than the Kerguelen Island type. 



2. Rhizoclonium crassipellitum robustum G. S. West, Jour. Bot. 42: 283. 1904. 



In fresh or brackish water, often in association with RhhopJiora. New Provi- 

 dence, South Bimini, Exuma Chain, Cat Island, and Mariguana : — Barbados. Type 

 of variety from Barbados. 



The filaments of the Bahamian specimens have a diameter of 39-90 fi. Ap- 

 parently distinct from the plants here referred to R. Hookeri. 



3. Rhizoclonium riparium implexum (Dillw.) Eosenv. Mecld. om Gronland 3: 



915. /. 34. 1893. 

 Conferva implexa Dillw. Brit. Conf. 46. p?. B. 1809. 



In association with RhizopJioro, often clothing its roots. Berry Islands and 

 Bimini (det. F. S. Collins) : — widely distributed. Type from Ireland. 



4. Rhizoclonium hieroglyphicum (Ag.) Kiitz. Phyc. Germ. 206. 1845. 



Conferva MeroglypMca Ag. Flora 10: 636. 1827. 



In fresh-water pools. New Providence {Brace) : — widely distributed. Type 

 from Carlsbad, Austria. 



3. *CLAd6pH0RA Kiitz. Linnaea 17: 91. 1843. 



Plants of fresh or brackish water, unattached, usually floating : filaments much bent 

 and curved ; main filaments 60—120 fi in diameter, the ramuli 

 20-40 /i ; cells 3—6 times as long as broad. 1. C.fracta. 



Marine. 



Ultimate ramuli nearly as stout as the main filaments. 



Filaments 35-95 fi in diameter ; plants spongiose-cespi- 

 tose or spongiose-funicular ; cells mostly 8-10 times as 

 long as broad. 2. C. crispule. 



Filaments 150-320 fi in diameter, plants cespitose, rather 

 rigid, dark green or blackish green, blackening after 

 collection, known only in association with a filament- 

 ous fungus endophytic in its cell walls. 3. C fulifjinosa. 

 Ultimate ramuli much more slender than the main filaments. 

 Plants bright green or light green. 



Ultimate ramuli more or less fascicled, 50—120 fi in 



diameter, constricted at septa. 4. C. fasctcularis. 



Ultimate ramuli not fascicled, 16-40 n, in diameter. 



Virgate in habit. 5. C. nitida. 



Dichotomous or trichotomous, not virgate. 6. C crystalUna. 



Plants yellowish : cells 4-10 times as long as broad, often 

 somewhat enlarged at distal end ; diameter of main 

 filaments 60-80 /x, the often secund ultimate ramuli 

 18-50 11. 7. C. luteola. 



1. Cladophora fracta (Vahl) Kiitz. Linnaea 17: 91. 1843. 



Conferva fracta Vahl, FI. Dan. 6": 7. pi. 946. 1787. 

 P Conferva vagabimcla L. Sp. PI. 1167. 1753. 



Floating on brackish ponds. New Providence and Berry Islands : — widely dis- 

 tributed. Type from Denmark. 



* The treatment of the recognized Bahamian species is based chiefly upon deter- 

 minations by Mr. F. S. Collins. 



