130 
LS 
(o4) 
bo 
86. S. undulata Bail. V.H. Syn. tab. XLII, fig. 2. 
Found only in a sample from K Kt. 
Area: the coasts of N. America, Europe, Red Sea, Ceylon, Hawaii. 
Thalassiothrix Cl. & Gr. 
87. Th. Frauenfeldi Grun. V.H. Syn. tab. XXXVII, figs. 11—!2. 
Only found in a sample from TK. 
Area: Atlantic Ocean, Mediterranean, Red Sea, Indian Ocean, Malay Archi- 
pelago, China Sea, Pacific Ocean (Ostenfeld). 
Asterionella Hass. 
88, A. notata Grun. V.H. Syn. tab. LI, fig. 2. 
KKt, s.1. (8 samples). 
Area: Honduras, Barbadoes, Adriatic. 
Achnanthoideae. 
Achnanthes Bory. 
89. A. angustata Grev. Cl. Vega Exp. tab. XXXV, fig. 2. 
KON, KKt, LN (6 samples). 
Area: Californian guano, Ceylon, Samoa. 
Occurs sometimes somewhat smaller. 
yO. A. brevipes Ag. var. intermedia Kitz. — A. subsessilis Ktz. 
Perag. Diat. de Fr. tab. I, figs. 19—21. 
Found only in a sample from LN. 
Area: in algis marinis passim (de Toni). 
91. A. javaniea Grun. var. rhombica Grun. Tab. nostr. I, figs. 15 & 16. 
KKt, LN, s.1 (4 samples). 
Area: Java, China, Madagascar. 
As certainly belonging to 4. jav. var. rhomb. I refer my fig. 15 
in shape agreeing with the figure by Petit in Diat. prov. de Madagascar 
fig. 8. My fig. 16 (Epitheca) shows two longitudinal lines and a blank 
spot at each end of the valve on the same side of pseudoraphe. In 
Achn. Bengalensis Grun. such spots are characteristic according to Cl. 
Syn. Il, p. 196, but here ihe fact is that ,at each end of the valve is a 
small blank spot on both sides of the area‘. I have seen a similar valve 
in connection with a hypotheca showing a conspicuous bifid stauros in- 
the same slide from which my figure is drawn. I suppose that this valve, 
in spite of the longitudinal lines being remoted from the margin is .an 
epitheca of . javanica which then possess similar ,blank spots“, though 
