NEW MYXOPHYCEAE FROM PORTO RICO 53 



Schizothrix mellea sp. nov. 



Filaments associated with other alg-ae, prostrate to somewhat 

 erect, and at times slightly fasciculate, 400-800 |j long-, 8-15 n 

 diam., moderately and alternately branched; apices acuminate, 

 closed ; trichomes 1-3, or as many as 6, within a sheath, 3.3-3.6 n 

 diam., straight or arcuate, with the filaments not congested, 

 slig-htly constricted at the cross-walls; cells 2-2.5 times as long 

 as broad, homogeneous to finely granular, pale aeruginous to 

 slightly honey-colored; cross-walls thin, but conspicuous; apical 

 cell blunt-conical ; sheath homogeneous, hyaline, but soon chang- 

 ing to dense lionej'-color. 



Growing on red soil by the road to Hacienda Catalina, Pal- 

 mer, no. 776 a, type, and no. 778 a; on rocks at Maricao, nos. 

 1031 a, 1033 a, 1037 c, and 1043 a; on soil by the road to Monte 

 Montoro, Maricao, nos. 1071 c and 1077 d ; on rocks near Maricao, 

 no. 1142 ; on earth at Hacienda Holm, Mayagiiez, nos. 1177 a and 

 1179 a. 



Schizothrix mellea, as proposed here, is very close in the 

 structure of- the trichome to Schizothrix {Symplocastrum) 

 Friesii as described by Gomont,^^ but it is much smaller (less 

 than one millimeter long) than that species, and lacks the rigid, 

 erect, spine-like habit which that species generally, though not 

 always, assumes. 



Schizothrix mellea minor var. nov. 



Trichomes 2.2-2.4 n diam. ; filaments shorter than in the 

 species, otherwise the same as the species. 



Growing on rocks, Maricao, no. 1032 a, type ; Arroyo de los 

 Corchos, no. 1732. 



Schizothrix rosea sp. nov. 



Filaments long- and flexuous, remaining simple and with a 

 single trichome for some time, later with two trichomes, and 

 more or less branched ; trichomes 6-6.2 |j diam. ; sheath narrow 

 and homogeneous, hyaline at first, changing to pale purplish 

 pink, becoming thicker and more or less lamellose at maturity. 



Growing on rocks in the vicinity of San Lorenzo, no. 519, 

 type; on earth. Hacienda Holm, Mayagiiez, no. 1176. 



Schizothrix thelephoroides minor var. nov. 



Filaments 300^00 \x long, alternately and somewhat pro- 

 fusely branched, 15-20 \x diam., not forming a definite stratum, 



i--'Gomont, Ann. Sci. Nat. Bot. VII. 15: 316. 1892. 



