Marine Diatoms 27F 
Rhabdonema Kitz. 
Rhabdonema adriaticum Kiitz. 
Sch. Atlas, Pl. 217, fig. 17-26; Van Heurck Syn., Pl. 54, figs. 11-13. 
Very prolific at Stations 23 and 43a. 
Rhabdonema arcuatum Kitz. 
Sch. Atlas, Pl. 220, fig. 17-26. 
Found at Stations 23, 43a, 43b, 43c and 41. 
Rhabdonema minutum Kiitz. 
Van Heurck Syn., Pl. 54, fig. 17-21. 
Found at Stations 41, 48a, 4386 and 438c, generally abundant; typical at 43a. 
Rhabdonema Torellii Cl. 
Sch. Atlas, Pl. 218, figs. 18-20; Cl. Arct. Diat., Pl. 4, fig. 20. 
The above two illustrations are given to show that R. Japonicum Brun can 
aoe be separated from this, but is probably merely a fossil variety. Found at 
tation 23. 
Rhizosolenia Ehr. 
Rhizosolenia styliformis Bright. 
Perag. Rhizo., Pl. 4, figs. 1-5. 
Found in two plankton hauls, Stations 6b and 12d, there very abundant. 
Rhoicosigma Grun. 
Rhoicosigma mediterraneanum Cl. 
Perag. Pleuro., Pl. 9, figs. 28-31; Cl. N. and R. Diat., Pl. 1, fig. 9. 
My specimens are small and otherwise not quite typical. Found at stations 
20b-c. 
Rhoicosphenia Grun. 
Rhoicosphenia curvata (Kiitz.) Grun. 
Van Heurck Syn., Pl. 26, figs. 1-4. 
Found abundantly at Stations 20b-c, 41, 41c and 430. 
Rhopalodia Miller 
Rhopalodia gibba (Kiitz.) O. Mull. 
Sch. Atlas, Pl. 253, figs. 1-17; Van Heurck Syn., Pl. 32, figs. 1-5. 
Found only at Station 43c. 
Sceptroneis Ehr. 
Sceptroneis gemmata Grun. 
Van Heurck Syn., Pl. 37, fig. 3. ; 
Van Heurck, in Treat., p. 332, makes this Grunoviella gemmata (Grun.) V. 
H. Found at Station 43a. 
Scoliopleura Grun. 
Scoliopleura latestriata (Breb.) Grun. 
Sch. Atlas, Pl. 261, figs. 4-5, misnamed; Van Heurck Syn., Pl. 17, fig. 12. 
Found at Station 23, scarce. eR 
Scoliopleura tumida (Breb.) Rab. | 
-- Sch. Atlas, Pl. 262, figs: 1-6; Van Heurck Syn., Pl. 17, figs. 11, 13. ° 
Found at Station 43a, also scarce. i 
