NEW MYXOPHYCEAE FROM PORTO RICO 



51 



cylindrical l)raiicli('s with acute apices, 10-1.") ^ thick; trichomes 

 single within a sheath, or in the region of branching at times 

 with 2-3 in a sheath, 4.r)-r) [\ diam., deeply constricted at the 

 cross-walls, pale aeruginoiis to grayish ; cells quadrate to 2 times 

 as long as the diameter; homogeneous, linely or coarsely gran- 

 ular, according to age ; apical cells blunt-conical ; sheaths hya- 

 line, homogeneous, or slightly lamellose in some old filaments. 



Growing among moss at ' ' Campo ' ' in Mariaco, no. 1228, type. 



The combination of characters in these plants, as diagnosed 

 above, is such as to exclude it from any of the previously de- 

 scribed genera. It then becomes a matter of either creating a 

 new genus, modifying the already recognized ones, or waiving 

 some of the characters. I have decided to do the last, and place 

 it with Hypheothri.r, with the fasciculate habit. 



Hypheothrix symplocoides sp. nov. 



Plate 10, figure 97 



Filaments 8-10 \i diam., prostrate and free at the base, grow- 

 ing erect and coalescing firmly into acute conical fascicles, seem- 

 ingly many trichomes in a common sheath, but the individual 

 filaments containing but a single trichome, very distinct below, 

 and in j)art remaining- comj^letely distinct throughout; fascicles 

 about 1 mm. high ; trichomes 2.4-2.8 n diam., not constricted at 

 the cross-walls; cells 1.5-3 times as long as the diameter, bright 

 aeruginous, homogeneous to finely granular; sheath hyaline, 

 almost transparent, smooth, homogeneous. 



Growing on the soil in a forest near Hacienda Catalina, Pal- 

 mer, no. 760, type, and no. 754. 



The material of this species possesses the characters closely 

 relating it to at least four established genera. Its size, color and 

 especially its fasciculate habit of growth, are typical of the 

 genus Syniploca Kuetz. but the sheaths are too much thickened 

 to be characteristic of that genus and the characteristic branch- 

 ing is lacking. Nothing would prevent its alliance with Gomont's 

 genus Sijmplocastruni, but its lack of multiple trichomes within a 

 common sheath excludes it from that genus as emended by 

 Kirchner." It is a typical SchizotJirix in the sense of Forti^^ 

 with the exception of the color of the sheaths, and in the sense of 



11 Engler & Prantl, Naturl. Pflanzenfam. li^: 69. 1898. 



12 In De Toni, Sylloge Algarum 5: 359. 1907. 



