— 30 — 



Gomphonema Ag. (1824), Cl. Syn. I, p. 178. 



8. G. parfnlum Ktz. V. H. Syn. tab. XXV, fig. 7. 



Klong Sarlakpet. 



var. sideropus Ktz. V. H. 1. c. figs. 4 — 5. 

 Klong Majum, Lem Dan. 



Area: the main species ubiquitous, var. micropus: Europe, America. 



Obs. In a sample from Lern Dan I found specimens of G. parvulum, 

 which are nearest to var. subcapitata (V. H. 1. c. fig. 11), but propor- 

 tionately broader. In V. H.'s figure the rate between length and breadth 

 is 1 3 : 3 ; in the present form it is 14:5. 



9. G. gracile Ehr. forma major V. H. Syn. tab. XXIV, fig. 12. 

 var. naviculoides (W. Sm.) Grun. V. H. I.e. figs. 13 — 14. 



Klong Prao, Klong Munsé, Klong Son, Koh Samit, Lem Dan. (15 samples.) 

 Area: Europe, America, Java, New Zealand. 



10. G. entolejuin Öst. sp. nov. tab. nost. fig. 4. 



L. up to 0,065 mm., B. up to 0,01 mm. Striae 10 in 0,oi mm. 



Striæ short, marginal. Unilateral stigma present, but hardly 

 visible. By its marginal striæ and consequently large area this very 

 characteristic species reminds of G. Brasiliense Grun. (V. H., Syn. 

 tab. XXV, fig. 17) and G. Puiggarianum Grun. (V. H., 1. c. fig. 18) 

 and perhaps it might be considered an intermediate form between 

 those two species, provided they also possessed an unilateral stigma. 

 But as this is discernible only with difficulty in G. entolejum, its 

 presence in the two mentioned species is still conceivable. 



Klong Prao, Klong Munsé, Klong Majum, Klong Sarlakpet. (5 samples). 

 In some of these samples not rare. 



Anomoeoneis Pfitzer (1871) Cl. Syn. II, p. 5. 



11. A brachysira (Bréb.) Grun. V. H. Syn. tab. XII, figs. 8-9. 

 Klong Prao, Klong Son, Klong Munsé, Lem Dan. (9 samples). 

 Area: Greenland, Europe. 



12. A. exilis (Ktz.) Grun. V. H. Syn. tab. XII, fig. 11. 



Lem Dan (4 samples). 

 Area: Greenland, Europe. 



Navieula Bory (1822). 



Orthostichæ GI. Syn. I, p. 107. 



13. N. cuspidata Ktz. var. lanceolata Grun. enfr. O. Müll. El Kab 



tab. XII, fig. 18; tab. nostr., fig. 2. 



