77 



WELWITSCH'S AFRICAN FRESHWATER ALG^E. 



By W. West, F.L.S., and G. S. West, A.R.C.S. 



(Plates 365-369.) 



(Continued from p. -12.) 



XI. — Desmidiace^. 

 1. Gonatozygon De Bary (1856). 

 1. G. Ralfsii DeBary, Couj. 76-7, t. iv. f. 23-25 (1858). Long, 

 cell. 217 fj- ; lat. 18-5 /j. ; lat. apic. 15 n- 



Pungo Audougo. Inter Bittfachasjiermiim [iracilliiituin , ad lapides 

 submersas in rivulo de Tangue ; May 1857. No. 3. 



2. Cylindrocystis Menegh. (1838). 



1. C. CRASSA DeBary, I.e. 74, t. vii. C (1858). Long. 35 iu. ; 

 lat. 25 ju. 



Pungo Andongo. Ad latera boreal, et occid. de Pedra Songue ; 

 April, 1857. No. 12. 



3. Penium Breb. (1846). 



1. P. OBLONGUM De Bary, /. c. 73, t. vii. G, f. 1, 2 (1858). Long. 

 65-80 ^ ; lat. 22-24 i^. 



Golungo Alto. Ad margines stagnorum rivi Cuango ; Aug. 1857, 

 No. 155. 



Huilla. In paludibus exsiccandis ; April 1860. No. 176. Morro 

 de Lopollo ; Febr. 1860. No. 192. 



2. Penium sp. Long. 28 n* ; lat. 11*5 /^ ; this is probably P. 

 Mooreanum Arch., but not seen in sufficient quantity for accurate 

 identification. 



Huilla. Inter VtrUulariam ecalcatatam, Morro de Lopollo; 

 April, 1860. No. 179. 



8. Penium sp. Long. 26 f*. ; lat. 16 /x. 



Huilla. Prope lacum Ivantala ; March, 1860. No. 17. 



4. P. cuRTUM Breb. in Kiitz. Species Abjitruni, 167 (1849). 

 Clusteriuin 6'?<^f(f/u Breb. (1840) ; Kiitz. (1845). (Josniariion curium 

 Ralfs, Brit. Desm. 109, t. xxxii. f. 9 (1848). Long. 31-36 /x ; lat. 

 18-19 f*. 



Pungo Andongo. In pascuis spongiosis breve graminosis juxta 

 rupes gigant. pr. Catete ; May 1857. No. 111. 



Huilla. Morro de Lopollo ; Febr. 1860. No. 192. 



5. P. adelochondrum Elfv. in Acta Soc. Fauna et Flora Fenn. 

 V. 2, no. 2, 17, t. i. f. 13 (1881). All the examples have a faintly 

 retu.se apex; long. 38-5— 12 /x ; lat. 14-15 /x ; lat. apic. 8-5-9'5 /x. 



Huilla. In uliginosis editioribus prope Humpata, Empalanca 

 et Lopollo, plagas spongiosas unacum Eriocauloneis, Xyridibus et 

 Utriculariis constituens ; May 1860. No. 15. 



6. P. variolatum, sp. n. (tab. 368, fig. 23). P. parvum, 

 diametro 4-plo longius, ad medium leviter constrictum, apices sub- 



