Hapalosiphoii\ xvi. siROSiPHONiACEiE (West). 369' 



nosis editioribus, prope Humpata, Empalanca et Lopollo ; May 1860.. 

 No. 15. 



4. H. Welwitschii W. et G. S. West in Journ. Bot. 1897, p. 242.. 



PuNGO Andongo. — Inter Batrachospermum graciUhium in rivulo de 

 Tangue ips. Prtesidii ; May 1857. No. 3. 



This species may be compared with H. hihernicus W. et G. S. West 

 (in Journ. R. M. S. 1896, 103), from which it differs in the longer 

 cells of the primary filaments ; in having much fewer branches, which 

 are also shorter and not flexuose ; moreover, the cells of the branches^, 

 as well as the heterocysts, never attain the length of those of 

 //. hibernicus. Compare also with //. Intricatus West. 



2. STIGONEMA Ag. (1824). 

 The cells of this genus are protoplasmically continuous thi"ough- 

 out the whole plant, a fine strand of protoplasm, passing from 

 cell to cell along the middle of the filament, effecting this con- 

 tinuity. This is best seen in plants that have been dried and 

 soaked out, the cells then appearing like beads on a string. These 

 connecting threads ai'e not visible in living plants, but in becoming 

 dry the protoplasm shrinks away from the minute canal along 

 which it passes through the septa, and on soaking again does not 

 reattain its natural position. 



1. S. ocellatum Thur. in Ann. Sc. Nat. 6^ ser. Bot. i. 38D 

 (1875) ; W. et G. S. West in Journ. Bot. 1897, p. 243. 



Conferva ocellata Dillw. Brit. Conferv. 60-1, Supp. pi. D (1809). 

 J^irosiphon ocellatus Kiitz. Spec. Algar. 317 (1849) ; Tab. Phyc. ii. 

 (1850-2), 11, t. 37, f. ii. 



PuNGO AxDONGO. — A small form ; in small quantity amongst 

 Zygnema sp., growing on tufts of Scytonema Myochvous var. rhoro- 

 gi-ajihicum, on rocks on the northern and western sides of Pedra 

 Bongue ; April 1857. No. 153. 



Forma major W. et G. S. West in Journ. Bot. 1897, p. 243. 



A large and finely developed aquatic form. 



HuiLLA. — Inter Utriculariam, Morro de Lopollo ; April 1800. No. 

 179. In paludibus exsiccandis ; April 1860. No. 176. 



2. S. flexuosum W. et G. S. West in Journ. Bot. 1897, p. 243. 

 HuiLl.A. — Inter Hapt doslphonon luteolum et Jlicrosporam Lofyrenil, 



etc., in uliginosis editioribus prope Humpata, Empalanca et Lopollo. 

 plagas spongiosas unacum Eriocauloneia, Xyridibus, et Utriculariis 

 constituens ; May 1860. No. 15. Etiam Morro de Lopollo ; May 

 1800. No. 182. 



This is distinguished from S. panniforme (Ag.) Born, et Flah. by its 

 habit, its very different branching, its almost colourless sheath with 

 smooth exterior, and by the round apices of the branches, as well as 

 by its somewhat smaller size. 



3. S. minutum Hass. Brit. Freshw. Alg. i. 230 ; ii. t. Ixvii. f. 3,. 

 4 (1845) ; Born, et Flah. in Ann. Sci. Nat. 7"^ serie, Bot. v. 

 72-74 (1887) ; W. et G. S. West in Journ. Bot. 1897, p. 243. 



Scytonema minutum Ag. Synop. Algar. Scandin. 117 (1817). 

 HuiLLA. — In graminosis paludibus juxta rivulum de Lopollo ; April 

 1860. No. 180. 



