11 (i W. B. TURNKK, FHESH-WATER ALG.E OF EAST INDIA. 



Note. The above plants Nos. 46 — 54 form an interesting series, all being evi- 

 dently related yet differing in material points from one another, and agreeing in bther 

 details with those species of which S. margaritaceum Ehk. and S. rotula Nordst. are 

 t lie extremes. 



55. S. truncatnni, n. sp. S. minus, fere tam longum quam latum; semicellulis ellipticis, 

 basi et apice aequaliter rotundatis, 3-gonis; angulis paullo productis, truncatis, breviter 

 dentatis; semicellulse apice verrueis (a vertice triangulatiin positis) ornata 1 , reliqua 

 frondis laavi; margine basis sinuata; sinu brevi, acuto, extrorsum valde ampliato. A 

 vertice 3-gonum, lateribus paullo ineavatis, apieibus truncatis. 



Long. et lat. 21) — 30, lat: isth. 10 /a (fide G. C. W.). 



T. XIII, f. 20, after Waluch Mscr. No. 266. 



In general outline this agrees fairly well with the variety {var. Ii Wolleanum 

 N<>n.) of S. asperum, figured by Wolle (Desm. U. S. A. p. 127, t. XLII, f. 7, 8) 

 which although related to that species, is certainly not the form of BuÉBlSSON ifi pro- 

 boscideum exclus.). Wallich distinctly states »frond smooth», all the forms of S. 

 asperum, as the name indicates, being rough and granular. This form has the sides 

 crenato-sinuate only, and seems intermediate in form between Brébisson's species aspe- 

 rum and scabrum. 



56. S. furcatum (Ehrb) Bréb. (Liste p. 136, 1856; Arch. in Prit. Inf. p. 743; Xanth. 

 furcatum Ehrb. Abhl. Berl. Akad. p. 318, 1833; Infus. p. 148, t. X, f. '25; Meteorp. 

 p. 12, t. I, f. 21; Staur. spinosum Bréb. in Ralfs Br. Desm. p. 143, t. XXII, f. K; 

 Phyeastrnm furcigerum Ktz Phyc. Germ. p. 138, 1845; Asteroxanthium furcatum Ktz. 

 Sp. Alg. p. 183, 1849). Forma Indica, n. f. 



Long. 23, lat. 18 (s. proc); long. 30, lat. 28 (c. proc.) lat. isth. K. 5 ,«, fide G. 

 C. W. Mscr. No. 222. T. XIV, f. 6. 



In this form the processes at the angles are normal in number, but the sub- 

 sidiary processes are more sub-marginal than dorsal in position; this is seen in the 

 vertical view, in which they appear very short. 



Raneegunge, Nov. 1855; G. C. W. 



Note. The Asteroxanthium bisenarium of Kutzixg (Spec. Alg. p. 183, 184S 

 (non Xanth. bisenarium Ehrb., On Bailey, p. 46 Verbr. Amer.) = Xanth. — No. 3, 

 Bailey Am. Bacill. j>. 2i)l, t. I, f. 16, which is most certainly this species! Referring 

 to Ehrexbergs critical list of Bailey's forms on p. 46 Verbr. 1843, I tind that he 

 refers this to his Xanth. coronatum, p. 138, No. 259, t. IV, f. 26, 1. c; which is cer- 

 tainly different from Bailey's icon, and is really = St. furcigerum Bréb., in Menegh. 

 Synops. ]>. 216; so that the specific name coronatum of Ehr. is invalid. This is one 

 of several instances in which Ehrexberg has failed to recognize his own species, or 

 has described the same plant by different names! 



57. S. triangulare, n. sp. 8. parvum, quinta parte longius (piam latum; semicellulis cu- 

 neatis, apice leniter rotundatis, ventre paullo inflatis; triangulatis, quoque angulo pro- 

 céssubus binis sub-verticalibus positis apice bidentatis vel furcatis instructo; membrana 

 tota glabra; sinu amplissimo, fere rectangulo. A vertice visum triangulare, processubus 

 tribus planis tribus elevatis. 



