- 123 



Hemiaulus Ehb. 



44. H. Heibergii Cl. GL Diat. Java. tab. I, fig. 4. 

 KKm, KKt (2 samples). 



Area: Japan, China, Indian Ocean, Arafura, Malay Archipelago, Tropical 

 Atlantic. 



Terpsinoë Ehb. 



45. T. americana Ralfs. A. S. Atl. tab. CC, fig. 9. 

 Solitary in a sample from KGg. 



Area: Venice, Florida, Neuse River, Cape of Good Hope, Yokohama, 

 Australia, Samoa. 



Rutilaroideae. 

 Rutilaria Grev. 



46. R. recens Gl. Gl. New. Diat. tab. IV, fig. 57 a & b. V. H. Syn. 

 tab. CV, fig. 9. Tab. nostr. 1, fig. 5. 



KKm, KMn-CLt, KS (5 samples). 

 Area: Galepagos. 



As it may be seen of my figure compared with those quoted above 

 by Cleve and Van Heurck the present form is somewhat more elegant. 

 Cleve (I.e. p. 19) figures and mentions some „ strongly marked puncta". 

 which are not very conspicuous in Van Heurck 's figure and that I have 

 not seen in my specimens. Van Heurck thinks that the somewhat 

 unsymmetrical sculpture shown in his figure „ ferait croire à une Euodiée". 

 Cleve whose figures do not show any unsymmetrical sculpture however 

 points out that his Rutilaria recens is „very allied to the genus Cymato- 

 sira Grun., of which the only known species C. Lorenziana Grun. has 

 also marginal bristles". As my form do not possess „strongly marked 

 puncta", i. e. the character which should entitle its affinity to Rutilaria, 

 and as it does not show an unsymmetrical sculpture, I am most inclined 

 to think it allied to Cymatosira Grun. 



B. Pennatae. 



Tabellarieae. 



Rhabdonema Ktz. 



47. R. adriaticum Ktz. V. H. Syn. tab. LIV, figs. 11-13. 

 Common in the samples (25) from KKt. 

 Area: ubiquitous. 



