CODIACEAE. 611 



dichotomy or pseudo-dichotomy, or sometimes apparently terminal, the filament 

 continued by a lateral innovation; zoospores numerous (about 200-500 to a 

 sporangium), ellipsoid or ovoid, 20-40 ^ X 20-25 ju. 



Green Cay, W. O. Coker, June 30, 1903, dredged In 4 fathoms,^ — a small amount 

 of material preserved In formalin. There Is a possibility that the plant belongs in 

 Oladophoropsis, but the terminal rather than intercalary sporangia and the large 

 zoospores, on some of which indications of a circle of cilia have been noted, have 

 suggested its reference to Bryohesla, the Javan type-species of which it resembles 

 closely, though the Bahamian plant is evidently longer and coarser, with filaments 

 twice as broad. 



Family 12. CODIACEAE. 



1. AVBAINVILLEA Decaisne, Ann. Sci. Nat. Bot. II. 18: 108. 1842. 



P'radelia Chauv. Eecherches 124. 1842. 

 Chloroplegma Zanard. Mem. E. 1st. Yen. 7: 290. 1858. 



Thallus eventually developing a flabellum (usually stlpitate). 



Fusco-nigrescent, yellowish brown, or tawny green ; surface subvelutinous, 

 spongiose, or strigose ; filaments of flabellum 28—70 n 

 in diameter. 

 Filaments of flabellum moniliform. 1. A. nigricans. 



Filaments of flabellum cylindric,' with a strong constric- 

 tion at base of each branch, rarely subtorulose. 2. A. longicauUs. 

 Olivaceous or cinereous ; surface smooth and compact ; fila- 

 ments of surface of flabellum 6-24 )i in diameter. 3. A. levis. 

 Thallus not developing a flabellum, forming more or less digi- 

 tate, sometimes capitate lobes, these commonly very irregular 

 in form, and often branching, diffluent, or anastomosing. 4. A. Rawsoni, 



1. Avrainvillea nigricans Itecaisne, loc. cit. 



Fradelia fuliginosa Chauv. Eecherches 124. 1842. 



Avrainvillea longicavUs Murr. & Boodle, Jour. Bot. 27: 70 p.p. pi. S28. 

 f. 1-5. 1889. [Excluding syn. lihipilia longicauUs Kiitz.] 



Common in shallow water, mostly on reefs or In places protected by reefs. 

 New Providence, Andros, Berry Islands, Great Bahama, Gun Cay, Eleuthera, Exuma 

 Chain, Mariguana, Caicos Islands, Castle Island, and Great Bagged Island : — Ber- 

 muda and Florida to South America. Type from lies des Saintes, near Guadeloupe. 



Forma fUlva M. A. Howe (in C. H. & S. Phyc. Bor.-Am. V,80) difEers from the 

 typical form in its thicker, more soongiose. and usually more cuneate flabellum, in 

 its flatter, broader, less differentiated stipe, and in the firmer-walled, usually 

 coarser, though often more tapering filaments, which are less regularly moniliform, 

 often more tortuous or zig-zag, more frequently and more divaricately dichotomous, 

 and nearly always yellow or yellowish brown rather than fuscous at maturity. 



2. Avrainvillea longicaulis (Kiitz.) Murr. & Boodle, Jour. Bot. 27: 70 p.p. 



188&. [Excluding all but syn. Shipilia longicaulis Kiitz.] 



Bhipilia longicauUs Kiitz. Tab. Phyc. 8: 13. pi. Z8. f. II. 1858. 

 Avrainvillea Mazei 'Murr. & Boodle, loc. cit. 



Common In shallow or moderately deep water, often with A. nigricans. New 

 Providence, Exuma Chain, Watling's Island, Mariguana, Caicos Islands, Castle 

 Island, Great Bagged Island, and Salt Cay : — ^Bermuda to Barbados. Type from 

 Antigua. 



3. Avrainvillea levis M. A. Howe, Bull. Torrey dub 32: 565. pi. SS. f. 1; 



pi. M. f. 8-10. 1905. 



Avrainvillea sordida Murr. & Boodle, Jour. Bot. 27: 70. 1889. Not A. 

 sordida (Mont.) Crouan; Maze & Schramm., Alg. Guad. 8'9. 1870-'77. 

 [Based upon Vdotea sordida Mont, in technicalities of publication.] 



Near low-water mark. Exuma Chain, Mariguana, and Caicos Islands : — Florida, 

 Cuba, and Jamaica. Type from Cave Cays, Bxuma Chain. 



