KHODOMELACEAE. 



567 



atropurpurea. 

 tcnui8sima. 

 polyrhiza. 



2. CHONDRIA Ag. p. p. Syn. Scand. xviii. 1817. 



Carpocaulon Kiitz. Phyc. Gen. 436. 1843. 



Chondriopsis J. Ag. Sp. Alg. 2: 794. 1863. 



Apices of ultimate ramuli acute, with growing points readily visible. 

 Plants erect, mostly 5 10 cm. high, without rhizoids except at base. 

 Primary branches more slender than the stout well-defined 

 main axes ; plants large, mostly 15-40 cm. high, yellow- 

 ish brown when dried. 1. C. littoralis. 

 Primary branches rather similar to the often poorly de- 

 fined main axes. 

 Plants blackish purple on drying, rather coarse, branch- 

 ing irregular. 2. C. 

 Plants yellowish red or dusky red on drying, more deli- 

 cate, branching sparsely virgate. 3. C 

 Plants low-cespitose, 2-3 cm. high or subrepent, with numer- 

 ous multicellular rhizoidal haptera. 4. C, 

 Apices of ultimate ramuli obtuse or truncate, with growing point 

 immersed and hidden in an apical pit. 

 The five pericentral siphons with conspicuous saucer-shaped, 

 dome-shaped, or cup-shaped thickenings of their anterior 

 end-walls, forming regular transverse crenate lines 

 bounding the even-ended bundles of siphons and visible 

 through the cortex. 

 Plants cespitose, the cushions 13 cm. high : main axes 

 mostly 0.22-0.35 mm. in diameter; apical tufts of fila- 

 ments inconspicuous. 

 Plants solitary or merely gregarious, mostly 3-8 cm. high ; 

 main axes 0.40.75 mm. in diameter ; apical tufts of tri- 

 choblasts conspicuous, often 0.75 mm. or more in length, 

 becoming yellowish brown or fuscous on drying. 

 Pericentral siphons without conspicuous thickenings of the 

 anterior end-walls (or such thickenings of only irregu- 

 lar and occasional occurrence). 

 Plants pink, purple, or yellowish red : main axes mostly 

 0.51.5 mm. in diameter ; ultimate ramuli mostly 0.35 

 0.75 mm. in greatest diameter. 7. C. 

 Plants usually yellowish brown ; main axes mostly 0.22- 

 0.32 mm. in diameter ; ultimate ramuli mostly 0.1-0.2 

 mm. in greatest diameter. 8. C. 



5. C. curvilineata. 



6. C. Collinsiana. 



dasyphj/Ua. 

 leptacremon. 



1. Chondria littoralis Harv. Xer. Bor.-Am. 2: 23. 1853. 



Chondriopsis littoralis J. Ag. Sp. Alg. 2: 795. 1863. 

 Carpocaulon littorale Kuntze, Eev. Gen. PI. 3 2 : 399. 1S98. 



Rather common on moderately exposed shores, near the low-w r ater mark, Now 

 Providence, Berry Islands, Great Bahama, Exuma Chain, Watling"s Island, Mari- 

 guana, and Caicos Islands : Florida and the West Indies generally. Type from Key 

 West, Florida. 



2. Chondria atropurpurea Harv. Ner. Bor.-Am. 2: 22. pi. 18E. 1S53. 



Chondriopsis atropurpurea J. Ag. Sp. Alg. 2: 801. 1863. 

 Carpocaulon atropurpureum Kuntze, loc. cit. 



In shallow water, especially in creeks and lagoons, commonly straw-colored when 

 living, Great Bahama, Great Exuma, Watling's Island, and Great Ragged Island: 

 Bermuda ; South Carolina ; Florida ; and the West Indies generally. Type from 

 Charleston, South Carolina. 



3. ? Chondria tenuissmia (Good. & Woodw.) Ag. Syn. Alg. Scan.], xviii. 1817. 



Fucus tcnuissimus Good. & Woodw. Trans. Linn. Soe. 3: 215. pi. 19. 1797. 



Carpocaulon tenuissimum Kuntze, loc. cit. 



Laurencia Baileyana Mont. Ann. Sci. Nat. Bot. III. 11: 63. 1849. 



Two specimens that we refer provisionally t<> ('. lenuissima differ consid- 

 erably from each other and from the English type of the species, in hal 

 texture, form and size of the cortical cells, etc. 



In shallow water, Rimini and Great Bahama: Massachusetts to Florida and 

 Cuba ; Europe. Type from southern England. 



