564 Howe: Phvcological studies 



very short anastomosing processes. [Plate 23, figure 2 ; plate 



24; PLATE 26, FIGURES 1-6.] 



Near low-water mark in the Bahama Islands : no. jg8 1, type 

 (Cave Cays, Exuma Chain, 19 February 1905, M. A. H.) ; nos. 

 14.17b and 3421b (Rose Island); no. 4186a (Stocking Island, 

 Exuma Harbor). 



Halimeda favulosa simulates in form, size and habit certain con- 

 ditions of If. tridens (Ell. & Soland.) Lamour. or of H. tridens 

 Monile (Ell. & Soland.) * but is easily and constantly distinguished 

 by the very large peripheral utricles (1 10—260// vs. 33—68// in H. 

 tridens) which, on drying, collapse or withdraw into the subtend- 

 ing and separating lime-cups, leaving the surface conspicuously 

 and rather beautifully favulose. In the character of the peripheral 

 utricles the species suggests H. macrophysa Ask., though its 

 utricles are sometimes even larger than in that, according to the 

 measurements given by Askenasy and by Barton, but it has the 

 size, form, and node-characters of the H. tridens group instead of 

 the H. Tuna-H. macrophysa alliance. It evidently bears a relation 

 to H. tridens similar to that of H. macrophysa to H. Tuna. In case 

 of three out of the four collection numbers cited above, H. favulosa 

 was found growing in company with H. tridens or H. tridens 

 Monile and resembling them so much in habit that the distinctive 

 characters escaped observation at the time of gathering. 



There is a possibility that Halimeda favulosa will prove to be 

 H. brevicaulis Kutz., f described from the Bahamas, but the 

 doubts in regard to this can probably never be resolved unless 

 Kutzing's specimen, which now seems to be lost, is found.]; H. 

 brevicaulis, according to Kutzing's figure and brief description, 

 might equally well be a form of the extremely variable H. tridens, 

 which is more abundant in the same region. The short stipe of 

 "brevicaulis" has no special significance, but the apparently flac- 

 cid habit and tapering branches, it must be admitted, are rather 

 suggestive of H. favulosa. Yet flaccid, decumbent conditions of 

 H. tridens occur. Kutzing describes the stipe of H. brevicaulis 

 as terete, while in all the specimens of H. favulosa that we have 



* Halimeda tridens Monile ( Ell. & Soland. ) 

 Corallina Monih Ell. & Soland. Nat. Hist. Zooph. no. //. 20. f. c. 1786. 

 tTab. Phyc. 8 : ll.pl. 2J. f. 2. 1S58. 

 % See " Addendum " on page 586. 



