EHODOMELACEAE. 575 



3. Lophosiphonia cristata Falkenb. Rhodoniel. 499. pi. 0. f. 7-10. 1901. 



Making a velvety coating on surf-beaten rocks, low-littoral. Berrj' Islands Mari- 

 guana, and Great Ragged Island : — St. Thomas and Mediterranean Sea. Tvpe from 



Naples. 



13. DIPTEROSIPHONIA Scliinitz & Falkenb. in Eng. & Prantl, 

 Nat. Pflanzenfam. 1-: 463. 1897. 



1. Dipterosiphonia dendritica (Ag.) Schmitz, loc. cit. 464. 

 ButcMnsia dcndriiica Ag. Syst. Alg. 146. 1824. 



Creeping on Chamacdoris and on Laurencia pai)illosa, Eleuthera : — American Vir- 

 gin Islands ; Brazil. Tj'pe from Brazil. 



14:. AMANSIA Lamour. Nouv. Bull. Sci. Soc. Philom. 1: 332. 1809. 

 1. Amansia multifida Lamour. loc. cit. i>l. 6. f. 2C, D, E. 



Usuallj' found waslied ashore, Eleuthera : — Florida to Brazil. Type from Santo 

 Domingo. 



15. HETEROSIPHONIA Mont. Prod. Phyc. Pol. Antarct. 4. 1842. 

 Trichoth AMNION KUtz. Pliyc. Gen. 415. 1843. 



Main axes uncorticated, mostly 65-130 ^ in diameter; fronds 



1-6 cm. long or high. 1. //. M'urdcmauni. 



Main axes strongly corticated, mostly 0.45-1.1 mm. in diam- 

 eter ; the brownish diaphragms of the central siphon visible 

 through cortex; fronds 4-18 cm. high. 2. //. Gibhcsii. 



1. Heterosiphonia Wurdemanni (Bail.) Falkenb. Rhodomel. 638. pJ. 16. f. 11. 



1901. 



? Callithamnion crispellum Ag. Sp. Alg. 2: 183. 1828. 



Dasya Wurdemanni Bail.; Harv. Ner. Bor.-Am. 2: 64. 2>?- l^C. 1853. 



Eesembling a species of Dasya, as pointed out on a later page. 



On corallines and various other algae, under shelving rocks, on roots of Rhizo- 

 pliora, etc., low-littoral or in shallow water, Berry Islands, Great Bahama. Bimini, 

 Gun Cay, Exuma Chain. Watling's Island, Mariguana, Caicos Islands, and Little 

 Inagua : — Bermuda and Florida to Barbados ; Adriatic and Mediterranean seas. Type 

 from Key West, Florida. 



2. Heterosiphonia Gibbesii (Harv.) Falkenb. Khodomel. 653. 1901. 



Dasya &ibbesii Harv. Xer. Bor.-Am. 2: 59. pi. 15 A. 1853. 



In tide-pools and in shallow water down to 2 meters or more. New Providence. 

 Berry Islands, Great Bahama, Andros, Eleuthera, Cat Island, Exuma Chain, and 

 Watling's Island : — Florida. Type from Key West, Florida. 



16. DASYA Ag. Syst. Alg. xxxiv, 211 (as Dasia). 1824. 



Ehodonema Martens, Reise nacli Venedig 2: 641. 1824. 



Dichotomous monosiphonous ramelli (2-4 mm. long) springing without order from 

 the firm cortex, densolv clothing the main axes or deficient in older parts. 

 Stichidia on 1- or 2-celled monsii)honous pedicels, translucent after dehiscence of 

 sporangia, showing central axis clearly. 

 Plants mostly 8-SO cm. high, main axes vaguely quasi- 

 pinnate or virgate ; cystocarps pedicellate. 1. D. peatccUdta. 

 Plants mostly 8-6.5 cm. high, subdichotomous ; ramelli 

 verv soft and mucous, more or less coherent or con- 

 fluent on drying; cystocarps sessile or subsessile. 2. D. Crouduinna. 

 Stichidia sessile or (m 1 -celled pedicels, rather opaque after 



dehiscence of sporangia and conspicuously zonate-anuu- . 



late. 3. D. ramosi8!^ima. 



