— 163 - 



This species occured in small gelatinous masses amongst Spirögyra 

 gracilis and S. neglecta in stagnant water in a riverbed. 



It is nearest to Cylindrocystis pgr antidata West & G. S. West recently 

 found in Ceylon, but it is distinguished by its smaller size, its less tape- 

 ring semicells, and its more open constriction. 



Penium Bréb. 



18. P. Digitus Bréb. in Ralfs Brit. Desm. p. 150, t. XXV, f. 3. Clo- 

 sterium Digitus Ehrenb. Penium lamellosum Kütz. P. navigium W. B. 

 Turner. 



Long. 188 ; lat. 54 p. 



Among Utricular i a in riverbed. 

 Area: Ubiquitous. 



19. P. australe Racib. in Rospraw. Akad. Umiej. Krakow. Wydz. 

 matem.-przy. ser. 2, vol. XXII, p. 367, t. VI, f. 27; West & G.S.West in 

 Journ. Linn. Soc. bot. XXXIII, 1897, p. 157, t. VIII, f. 16. 



Long. 80 — 75,«; lat. 43 — 44^; lat. constrict. 41—42//. 



In stagnant water in the jungle and in muddy ricefields. 

 Area: Singapore and Australia. 



20. P. cucurbitiiium Biss. in Journ. Roy. Micr. Soc. 1884, p. 197, 

 t. V, f. 7. 



Forma minor West in Journ. Roy. Micr. Soc. 1894, p. 4. 



Long. 55,5//; lat. 52^. 



In stagnant water with other Desmids. 

 Area: Europe. New Zealand (var.). 



21. P. curtum Bréb. in Kütz. Spec. Algar. 1849, p.' 167. Closterium 

 curtum Bréb. 1840. Cosmarium curtum* Ralfs 1848. 



■ Forma major Wille in Öfvers. af K. Vet.-Akad. Förh. 1879, no. 5, 

 p. 56, t. XIV, f. 73. 



Long. 58 fx ; lat. 28 p. 



On rocks in riverbed, abundant amongst Cosmarium keve. 



Area: Europe, N. America, W. Indies, India, Madagascar, and W. Africa. 



22. P. ftavicula Bréb. in Mém. Soc. Scient. Nat. Cherbourg, 1856, 

 IV, p. 146, t. 11, f. 37. 



Long. 32,5 fx; lat. 9,6 fx. 



In stagnant water in the jungle. 



Area: Europe, N. America. W. Indies, India, Burmah, Ceylon, Singapore 

 E. Indies, Sandwich Is., New Zealand and Australia. 



