145 297 
Pleurosigma 
169. P. australe Grun. Perag.“Diat de Fr. tab. XXXII, figs. 7—8. 
Found only in a sample from K Km. 
Area: Baleares, Between Aden and Bab el Mandeb, Sumatra, Java, Ceylon, 
Labuan. 
170. P. diminutum Grun. Perag. Pleuros. tab. VI, fig. 31. 
Found only in a sample from TK. 
Area: Baleares, Adriatic. 
171. P. elongatum W.Sm. W.Sm. Syn. tab. XX, fig. 199. 
KKm, KKt (3 samples). 
Area: Arctic Oceans, Atlantic coasts of America, Europe, Caspian Sea, 
Java, Sumatra, China, Tahiti. 
172. P. formosum W.Sm. W.Sm. Syn. tab. XX, fig. 195. 
KKt, K Mn—CLt, LN (10 samples), 
Area: Arctic Oceans, West Indies, Europe, Red Sea, Madagascar, Java, 
China, Ceylon, Labuan, Tahiti, Hawaii, Pacific Ocean, Galapagos. 
173. P. Grovei Cl. Perag. Pleuros. tab. VIII, fig. 1. 
Solitary in a sample from TK. 
Area: Malay Archipelago. 
I have. only found one moreover not complete specimen which dif- 
ferred form the typical form in being proportionately broader and in its 
more open striation. L. 0,43 mm., b. 0,051 mm., transversal striae 7,4 
in 0,01 mm., longitudinal strie 11,1 in 0,01 mm. 
174. P. navieulaceum Bréb. Cast. Chall. Exp. tab. XXIX, fig. 14 
(P. japonicum Cast.). 
KKm (2 samples). 
Area: North Sea, Mediterranean, Ceylon, Labuan, Java. 
175. P. Normanni Ralfs. V.H. Syn. tab. XVII, fig. 9. 
Found only in a sample from KKm, 
Area: Arctic Oceans, Atlantic coasts of America, Europe, Madagascar, 
Red Sea, Java, Sumatra. 
176. P. Nabecula W. Sm. var. intermedia W. Sm. Perag. Pleuros. 
tab. V, figs. 27-28. 
K Kt, KCg—K Lm (8 samples). 
Area: North Sea, Mediterranean, Port Jackson, Rio Grande. 
— — — var. subrecta Cl. Perag. Pleuros. tab. V, fig. 30. 
K Kt (3 samples). 
Area: Arctic Oceans, Baleares. 
