342 xi. desmidiace^e (West). [Clostei-ium 
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 Journ. 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. 
GrOLUNGO 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 num. Bero ; June 1859. 
No. 171. 
5. C. Leibleinii Kiitz. in Linnsea, viii. 596, t, xviii. f. 79 (1833) ; 
Ralfs, I.e., 167-8, t. xxviii. f. 4 (1848) ; W. et G. S. West in 
Journ. Bot. 1897, p. 79. 
Two forms : — 
Loanda. — In stagnis (Represa de Luiz Gomes) ; Feb. 1858. No. 136. 
Lat. 38 fji. 
Puxgo Andongo.— In stagnis prope Anbilla (Condo) ; March 1857. 
No. 177. Lat. 22 M . 
6. C. regulare 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 Nitdhv 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 cymbantham, Morro de Lopollo ; April 1860. 
No. 179. 
This species is readily distinguished from D. baculum Bre"b. by the 
much slighter basal inflation with no constriction above it, and by the 
different basal granules. 
6. PLEUROMNIUM Nag. (1849). 
1. P. sparsipunetatwn 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 '. sulcoronulatttm (W. B. Turn.) 
West, and P. conjunction (W. B. Turn.). 
