6Y G. I. PLAYFAiR. 503 



Diam. fil. 21-23, trich. 19-20, cell. alt. li-2i (plerunique 2/x). 



Lismore (32.3). 



An olive-green papyraceous stratum in great cjuantities on the 

 surface of a creek-pool, after heavy rain followed by heat. The 

 trichomes under the microscope were of a brilliant green colour 

 (very unusual in this family, but found also in 0. nigro-viridis) 

 or sometimes yellow-green. The tips of the filaments were some- 

 times rounded, but generally slightly constricted at the terminal 

 cell so as to be subcapitate. 



Phohmidium numarium, n.sp. (PL liv., f.6, 7). 



Stratum papyraceum olivaceum; filis angustissimis ai'cte in- 

 tricatis, vaginis tenuissimis, apicibus rotundatis ; trichomatis 

 dilute Ccoruleis, ad genicula valde constrictis, articulis brevissimis 

 disjunctis; cytoplasmate homogeneo. 



Diam. fil. 2, cell. alt. J-lJ/>t. Lismore (326). 



An olive-green papyraceous stratum on the curb-stone near a 

 down-pipe. The cells of the trichomes are disjoined and are of 

 the palisade-type, reminding one of a rouleau of coin, at most 

 quadrate before division, only to be distinctly made out with 

 the yV obj., the contents homogeneous, pale blue with a darker 

 band at the sides. 



Fam. NOSTOCACE/E. 

 Genus A n a b ^ n a Bory. 



ANABiENA AUSTRALICA, n.Sp. (PI. liv., f.8, 9). 



Trichouiata angusta, recta, libere natantia, ad genicula 

 levissime constricta; cellulis rectangularibus, adpressis, apicibus 

 truncatis; cytoplasmate dilutissime cseruleo jjiene hyalino, homo- 

 geneo vel rainutissime granulato; heterocystidibus angustis cylin- 

 draceis, apicibus rotundato-truncatis ; gonidiis angustis cylin- 

 draceis, apicibus rotundatis, lateribus parallelis, juxta hetero- 

 cystides ordinatis; cytoplasmate pulchre cyaneo, granulato. 



Cell. diam. 3-1, alt. 6-10, plerumque 8; heterocyst. diam, 4-5, 

 alt. 10^-15; gonid. diam. 5-7, alt. 19-32/x. 



Lismore (327, 337). 



Found free, floating. Trichomes narrow, very pale blue, 



