342 XI. DESMiDiACE^ (West). [Closteritmi 



2. C. peracerosum Gay, Essai Monogr. Conj. 75, t. ii. f. 18 

 (1883); Bull. Soc. Bot. Fr. xxxi. 339 (1884). 



Var. aethiopicum W. et G. S. West in Jonrn. Bot. 1897, p. 78, 

 t. 365, f. 9. 



PuxGO Andongo.— In stagnis prope Anbilla (Condo) ; March 1857. 

 No. 177. 



3. C. acerosum Ehrenb. Abhandl. Akad. Wissenschaft. Berlin 

 (1831), 68 (1832) ; Ralfs, Brit. Desm. 164, t. xxvii. f. 2. 



Vibrio acerosus Schrank. 



Var. angolense W. et G. S. West in Journ. Bot. 1897, p. 79. 

 GoLUNGO Alto.— Ad margines stagnorum rivi Cuango ; Aug. 1857. 

 No. 155. 



4. C. turgidum Ehrenb. Infus. 95, t. 6. f. 7 (1838) ; Ralfs, I.e., 

 165, t. xxvii. f. 3 (1848) ; W. et G. S. West in Journ. Bot. 1897, 

 p. 79. 



A shorter form than the typical one. 



MossAMEDES. — In stagnis exsiccatis ad ripas flum. Bero : June 1859. 

 No. 171. 



5. C. Leibleinii KUtz. in Linnsea, viii. 596, t. xviii. f. 79 (1833) ; 

 Ralfs, I.e., 167-8, t. xxviii. f. 4 (1848) ; W. et G. S. W^est in 

 Journ. Bot. 1897, p. 79. 



Two forms : — 



LoANDA. — In stagnis (Represa de Luiz Gomes) ; Feb. 1858. No. 136. 

 Lat. .^8 /x. 



PuxGO Andongo. — In stagnis prope Aubilla (Condo) ; March 1857. 

 No. 177. Lat. 22 /a. 



6. C. regulate Breb. in Mem. Soc. Imp. Sciences, Cherbourg, 

 iv. 148-9, 304, t. ii. f. 35 (1856). 



Forma minor W. et G. S. West in Journ. Bot. 1897, p. 79. 



HuiLLA. — Cum Nitellce sp. in stagnis pr. Catumba ; April 1860. 

 No. 189. 



Some algologists appear to confuse this plant with C. costatum 

 Corda ; it is, however, very distinct from it. 



5. DOCIDIUM Breb. (1844). 



1. D. trigeminiferum W, et G. S. West in Journ. Bot. 1897, 

 p. 79, t. 368, f. 32-34. 



HuiLLA. — In paludibus exsiccandis ; April 1860. No. 176. Etiam 

 inter Utriculariam cymhantham, Morro de Lopollo ; April 1860. 

 No. 179. 



This species is readily distinguished from D. hacuhim Br^b. by the 

 much slighter basal inflation with no constriction above it, and by the 

 different basal granules. 



6. PLEUROT^NIUM Nag. (1849). 



1. P. sparsipunctatum W. et G. S. West in Journ. Bot. 1897, 

 p. 79, t. 365, f. 10. 



PuNGO Andongo. — In stagnis prope Anbilla (Condo) ; March 1857. 

 No. 177. 



This species can be compared with P. subcoronulatum (W. B. Turn.) 

 West, and P. conjunctum (W. B. Turn.). 



