- 39 - 



Scalares V. H. 1. c. p. 391. 



60. FL scalaris W. Sm. cnfr. V. H. Syn. tab. LX, figs. 14-15. 

 Lem Dan (5 samples). In two of the samples not rare. 



Area: Europe, Australia. 



The size of the present form agrees with Grunow's var. minor (Gl. & 

 Grun. arct. Diat p. 83) found in Delaware river and in lagoons at Samoa. 



Obtusœ V. H. 1. c. p. 397. 



61. FL obtusa W. Sm. var. nana Grun. V. H. Syn. tab. LXV1I, fig. 3. 

 Lern Dan (4 samples). 



Area: the main species: Europe, America, Japan; var. nana only in 

 Haverfordwest (England) cnfr. V. H/s types No. 399. 



Lanceolatœ V. H. 1. c. p. 400. 



62. PL Palea (Ktz.) W. Sm. forma major. V. H. Syn. tab. LXIX, 

 fig. 22 e. 



var. minuta Bleisch. V. H. 1. c. fig. 23. 

 var. tenuirostris Grun. V. H. I.e. fig. 31. 

 var. debilis (Ktz.) Grun. V. H. I.e. figs. 28 — 29. 

 Lem Dan (4 samples), Koh Sam it. 



Area: the main species: Greenland, Europe, Abyssinia, Japan. 



63. !L intermedia Hantzsch. V. H. Syn. tab. LXIX, fig. 10. 

 Koh Samit. 



Area: Europe. 



Nitschiella Rabenh. 1864. V. H. Traité p. 404. 



64. FL longissima (Bréb.) Ralfs. V. H. Syn. tab. LXX, fig. 8. 

 Lem Dan. A fragment only. 



Area: Greenland, Europe. 



Coccochromaticæ. 



Fragilaria Lyngbye (1819). V. H. Traité p. 323. 



65. ¥. siamensis Ost. sp. nov. tab. nostr., fig. 19. 



L. 0,05—0,08 mm., B. in the middle 0,003—0,0035 mm., striæ 20 in 

 0,01 mm. Valve constricted in the middle and before the capitate 

 apices. Striæ parallel, obscure, absent in the apices. I am not 

 able to see any pseudoraphe. 



This characteristic form occurs in chains as Diatoma and Gramma- 

 tophora. The endochrom is granulary. 



Klong Munsé, Klong Son, Lem Dan. (5 samples). 



