— 173 



I h large numbers amongst C. lœve Rabenh. on rocks in a riverbed, and 

 also in stagnant water amongst various species of Spirogyra. 



62. C. subtriordinatum West & G. S. West in Journ. Bot. April 1897, 

 p. 122, t. 368, f. 11. 



Forma. (Tab. nostr. II, fig. 18.) 



Long. 22 — 24 fj. ; lat. 21 jl ; lat. isthm. 6 — 6,5 fi ; crass. 12,5 — 13,5 p. 



These forms only differ from the African examples in the somewhat 

 simplified central granules. They are distinguished from C. subpunctula- 

 tum Nordst. by their smaller size, much fewer and more acute granules, 

 and by the different arrangement of the central granules. 



In stagnant water in the jungle. 

 Area: W. Africa. 



63. C. pseudotaxichondrum Nordst. in Öfvers. af K. Vet.-Akad. Förh. 

 1877, no. 3, p. 20, t. II, f. 5. 



Var. siamense West & G. S. West, n. var. (Tab. nostr. Ill, fig. 26). 



Var. sinu apertiori, semicellulis minus angularibus, marginibus 

 lateralibus leviter undulatis, cum serie granulorum magnorum 3 

 trans medium semicellulæ uniuscujusque. 



Long. 26 fi ; lat. 29 p ; lat. isthm. 6,5 crass. 17/;. 



This variety is nearest to C. pseudotaxichondrum var. africanum 

 West & G. S. West (in Journ. Bot. May 1897, p. 173, t. 367, f. 14). 



In stagnant water in the jungle. 



Area: This species (with its varieties) is widely distributed in tropical and 

 subtropical regions. 



64. C. quadrifarium Lund in Nova Acta Soc. Scient. Upsala, ser. 3, 

 VIII, p. 32, t. III, fig. 12. 



Forma hexasticha Nordst. in Kongl. Sv. Vet.-Akad. Handl. Bd. 22, 

 no. 8, p. 49; C. hexastichwn Lund. I.e. p. 33, t. Ill, f. 13. 

 Long. 53^; lat. 41^; lat. isthm. 17^; crass. 29/*. 

 In stagnant water in riverbed. 

 Area of type: Europe. N. America, Ceylon. 



65. C. subdecoratum West & G. S. West in Journ. Linn. Soc. bot. 

 XXXIII, 1897, p. 164, t. VIII, f. 13. 



Long. 76^; lat. 54 — 59 «; lat. isthm. 19 — 22^. 



In stagnant water in the jungle. 

 Area: Ceylon and Singapore. 



66. C. pseudorthopunctatum West & G. S. West, n. sp. (Tab. nostr. 

 II, fig. 12-13.) 



G. parvum, circiter tarn longum quam latum, profunde con- 

 strictum sinu aperto et acutangulo ; semicellulæ subellipticæ, ventre 

 valde convexæ, dorso valde convexæ in medio subrectæ, angulis 



