50 R. Gronblad, New Desmids. 



III (1885) pi. 254 f. 5; West, N.-Amer. (1896) pi. 16 f. 2. - - var. tro- 

 picum Lagerh., Alg. bidr. II (1887) p. 198 fig. xyl.; B o r g e, Trop. 

 subtrop. (1899) pi. 1 f. 17. — forma B o r g e, ibid. pi. 1 f. 16. Nearest 

 to the above variety as a form with paired basal spines. - f. curvis- 

 pinum Cushm. in Rhodora VII (1905) pi. 64 f. 11. — f. callosum 

 C u s h m., ibid. pi. 64 f. 12. [In my opinion nearest to X controuersum: 

 the outline resembles X. cristatum]. — var. depauperatum W est, 

 Orkn. Shetl. (1905) pi. 1 f. 15—16; West, Mngr. IV (1912) pi. 110 f. 

 3—7 [Synon. = X. antil. forma West, Scott, frw. plankt. (1903) pi. 16 

 f. 1 — According to W e s t.j Here belongs apparently also X. antil. 

 forma West, Frw. alg. W-Irel. (1892) pi. 22 f. 2. 



X. fasciculatum, Larsen, E.-Greenl. (1904) fig. xyl., is nothing 

 more than a deformed form of X. antilopaeum. [Vide West, Mngr. 



IV page 66.] 



The following forms which originally were described 

 as forms of X. antilopaeum do not belong here: 



f. javanica Nordst, Alg. Mus. Lugd. Bat. (1880) pi. 1 f. 21 is = 

 X hastiferum Turn. — var. truncatum W o 1 1 e, Desm. U. S. ed. II 

 (1892) pi. 42 f. 3—5 is = X. tylerianum West. -f. javanica Johnson, 

 Rare Desm. U. S. II (1895) pi. 239 f. 10 is = X. hastiferum var. johns- 

 sonii West. - - forma W est, N.-Amer. (1896) pi. 16 f. 1 is = X. contro- 

 uersum West. — var. javanicum, Wilde m., Flor. Buitenzorg ( 1900) 

 p. 138 fig. xyl. is = X hastiferum, Turn. — var. incertum S c h m i d 1 e, 

 Alg. Nyassa (1903) pi. 2 f. 5, should be relegated elsewhere, according 

 to West (Mngr. IV p. 66.) 



Amongst these forms there are especially two viz. X. 

 hastiferum and X. controuersum that are very near to X. antilo- 

 paeum. Perhaps these would better be reunited with X. 

 antilopaeum. (Vide also Nordstedt N. -Zeal. page. 43!) — 

 Another species closely allied is our new species X. pseudo- 

 bengalicum nob. 



In the past X. antilopaeum and X. fasciculatum have 

 been confused, but they are always easily distinguished. 



X. pseudobengalicum nov. sp. Cellulae mediocres, medio 

 sinu profundo introrsum lineari, extrorsum valde dilatato 

 constrictae. Semicellulae a fronte visae subellipticae-trapezi- 

 formes, non angulosae; in marginibus lateralibus utrimque 

 spinae 3 longae graciliter sursum curvatae defixae sunt; area 

 centralis incrassata et conspicue luteola — fere rubrobrunnea 

 glabra, non porosa. A vertice visae rhomboidiformes utrimque 



