— 182 — 



Var. linearis Hansg. in Archiv Naturwiss. Landesdurchf. Böhm. Bd. 6, 

 1888, p. 268. 



In muddy ricefields. 



Area: Europe, N. America, W. Africa, Madagascar, Ceylon. 



104. S. acutiforiiiis Schröder in Forschungsberichten der Plöner 

 Biol. Stat. Heft 5, 1897, p. 17, t. II, f. 4. 



Var. spinuliferum West & G. S. West n. var. (Tab. nostr. IV, fig. 46 

 -49.) 



Var. cænobiis e cellulis 2 — 8 (plerumque 4) constituas; polis 

 cellularum spinis curvatis minutis 2 — 3 instructis. 



Long. cell, sine spin. 14 — 24//; lat. cell. 3,2—8,5/.«; long. spin. 

 1—5,7 fx. 



This variety occurred in large quantity amongst other Palmellaceœ in 

 stagnant water. The cœnobia were of all sizes and contained from two 

 to eight cells. All the cells possessed the lateral ridges characteristic of 

 this species. The small spines were very variable in number and position, 

 but were always of appreciable length and generally considerably curved. 



It bears a considerable resemblance to S. denticulatus var. linearis 

 Hansg., but is readily distinguished by the two prominent ridges on each 

 cell of the cœnobium. The spines at the poles of each cell are also 

 longer and more curved than in S. denticulatus Lagerh. 



105. S. quadricauda (Turp.) Bréb. in Mém. Soc. sc. nat. Falaise, 

 bot. 1835, p. 66: Ralfs Brit. Desm. 1848, p. 180, t. XXXI, f. 12. 



In stagnant water in riverbed. 

 Area: Ubiquitous. 



Rhaphidium Kütz. 



106. R. polymorphum Fresen. in Abhandl. der Senckenb. naturf. 

 Gesellsch. II, p. 199, t. VIII. 



Var. aciculare (A. Br.) Rabenh. Flor. Europ. Algar. Ill, p. 45. 

 In stagnant water in the jungle. 

 Var. falcatuin (Corda) Rabenh. 1. c. 

 With the preceding variety. 



Area: This species and its varieties are ubiquitous. 



107. R. convolutum (Corda) Rabenh. 1. c. p. 46. 

 Lat. cell'. 3,8 ju. 



With the preceding species. 

 Area: Europe. 



Selenastrum Reinsen. 



108. S. gracile Reinsch. in Abhandl. Naturhist. Gesellsch. zu Nürn- 

 berg, III, 1866, p. 65, t. IV, f. 3 a — 6. 



