498 Myxophycefe, Scytonemacese, Scytonema. 



Sound » Amer. bor. (Holden), Nova Anglia (Gomont), ins. « Reu- 

 nion » nuncupata (Jadin). — Forma Hansgirgiana (Hansg.) in 

 Sitzungsber. d. K. Bohm. Ges. fiir Wissensch. 1892, p. 222: tricho- 

 matibus 0,5-1 \i. crassis, curvatis, raro ramosis; vaginis arctis, 

 subtilibus, achrois, 1-1,5 rarius usque ad 2 {x. diam.; articulis 2-4- 

 plo diam. longioribus. In cochleis Patelhe, in rupibus vel in algis 

 calcareis, socia Gomontia polyrrhyza Born. et Flah. in litore 

 Dalmatise (Hansgirg). 



21. Piectonema gloeopliiium Borzi Alghe Papuas. in Nuova Notarisia 1169 

 III, 1892, p. 40. — Filis late expansis, tortuoso-intricatis, liyalinis 



aut pallidissime cffirulescentibus; vaginis arcLis, achrois; articulis 

 diam. brevioribus aut subnequalibus, ad 2-2,5 [x. latis; pseudora- 

 mulis solitariis, patentibus, raro geminis. 



Hab. in calvis capitum vetustis Papuasorum (Loria). — Sec. 

 cl. Borzi h;ec species Plectonemati Nostocorum videtur proxima 

 at satis a Bornetiana specie distincta. 



Species delenda. 



22. Plectonema Kirchneri Cooke in Grevillea XI, p. 75, 1882 = To- 

 lypothrix distorta Kuetz. 



SCYTONEMA Ag. [1824] p. 26 (Etym. scytos corium et nema filum), 

 Borzi Morf. in N. G. B. I. p. 368, 1878, Born. et Flah. Rev. III, 

 pag. 85, Kirchn. in Engl. und Pr. Nat. Pllanzenfam. pag. 79. 

 ConfervK, Inoconice, Calotrichis, Petalonematis, Ltjnghyoi, Dri- 

 losiphonis, Symphyosiphonis, Arthrosiphonis, Spermosira', Hy- 

 pheotrichis, Symploca^, Schizosiphonis, Leptotrichis, Tolypotri- 

 chis, Mastigonematis, Chrysostigmatis spec. Auct. — Fila pseudo- 

 ramosa; pseudo-rami solitarii vel gemini ex eruptione laterali tri- 

 chomatis formati, in intervallo heterocystarum interdum quoque 

 sed rarius, sub ipsis heterocystis, egredientes; trichomata intra 

 vaginam solitaria, recta; hormogonia terminalia, solitaria; spone, 

 in paucis speciebus tantum visas, sphgericse aut ovata3, exosporio 

 tenui et levi. 



Sectio I. EusCYTONEMA Born. et Flali. 1. c. pag. 89. — Vaginae homogenese vel 

 stratis parallelis formatse; cellularum disseiDimenta distincte perspioua. 



1. Scytonema crispum (Ag.) Born. Les Nostoc. heteroc. du Syst. Alg. 1170 

 de C. Ag. in Bull. Soc. bot. de France t. XXXVI, p. 156, J. Schm. 



