ECOLOGY AND TAXONOMY OF Holimeda 



137 



p. 85, Plate 45, Figs 1-2; Egerod (1952), p. 398, Plate 38, Pigs 19b-d; 



Hillis (1959), p. 352, Plates 2, 5-8, 11. 

 Holimeda discoidea v. platyloba Borgesen (1911), p. 134, Fig. 3; Borgesen 



(1913), p. 107, Fig. 86. 

 Halimeda discoidea f. intermedia Gilbert (1947), p. 126. 

 Halimeda discoidea f. subdigitata Gilbert (1947), p. 125. 

 Halimeda tuna Barton (1901), p. II p.p. 

 ? Halimeda cuneata f. digitata Barton (1901), p. 16, Plate 2, Fig. 9. 



^' r ^'^ ^ ^ -c^ \ \\ ih 



■. -' ^'^'^\-\^^\^ fc ^ " J' ' 



Fig. 41. i?. discoidea. A densely branched jslant witli some of the relatively large seg- 

 ments which conmionly occur in the lower portion of robust, mature thalli. Specimen 

 from Florida, 31 III 04, Howe 2964. 



Plants generally compact, forming cushion-like clumps but occasionally 

 loose, arising from a small but distinct holdfast region, to 18 cm tall; 

 calcification light; branching mainly ditrichotomous but polychotomous 

 from large segments; the basal first or second segments subcylindrical or 

 broadly cuneate and often of a substipitate nature ; other segments usually 

 plane, commonly discoidal to reniform but also compressed-cylindrical, 

 cuneate or subcuneate, the outer margin entire, undulating or occasionally 

 somewhat deeply cleft, to 29 mm long, 33 mm broad and averaging 

 0-75-1-25 mm in thickness. 



Cortex of two, occasionally three layers of utricles; outermost utricles 

 remaining firmly attached after decalcification for an average distance of 



