934 P. T. CLEVE, S. ATLANTIC PLANKTON. 



Nitzschia lineola Cl. (Fifteenth Ann. Rep. of the Fishery 

 Board for Scotland p. 300 f. 10). This species, found iu plank- 

 ton from the Färöe Channel, occurred between 42° S. 3' W. 

 and 45° S. 34° E. as well as froin 43° S. 73° E. to 40° S. 

 82° E. It occurs in long chains as A^. seriata. 



Nitzscbia (Trytolionella) migrans Cl. (Fifteenth annual report 

 of the Fishery Board for Scotland p. 300 f. 9). This form, 

 hitherto found only in the Färöe Channel, occurred very sparingly 

 at 45° S. 26° E. and 45° S. 34° E. The specimens from the 

 Southern Atlantic had closer Striae (16 in 0,01 m.m.) than speci- 

 mens from the Färöe Channel (11 in 0,01 m.m.). Length 0,027, 

 breadth 0,008 m.m. 



Odontella (?) antarctica (Ehb.) Grün. {Hemiaulus antarcti- 

 cus Ehe. 1844. Hern, amhiguus Janisch. A. S. Atl. CXLII, 

 f. 16 — 24. Exp. Gazeile PL XX f. 30. Eucampia halaustium 

 Castr. Challeng. Rep. PI. XVIII f. 5, 1886). This characteristic 

 antarctic form was found sparingly in some samples between 

 43° S. 1° E. and 43° S. 73° E. 



Pseudo-eunotia doliolus (Wallich) Grün. (Van Heurck, 

 Syn. PI. XXXV f. 22). This species occurred in almost all 

 samples, from 39° S. 10° W. to 32° S. 91° E. 



ßliizosolcnia alata Btw. Sparingly from 41° S. 6° W. to 

 33 S. 90= E. 



R. Bergonii H. Per. Very rare at 43° S. 1° E.; 45° S. 

 26° F.; 45° S. 34° E.; 44° S. 45° E.; 43° S. 73° E.; 42° S. 

 76' E.; 33° S. 90° E. 



Rhizosolenia inermis Castr. (Chall. Rep. Diät. PI. XXIV, 

 f. 7, 8, 10, 13. R. ohtusa Hensen. R. alata var. truncata 

 Gran.). Sparingly at 44° S. 9° E.; 45° S. 34° E.; 44° S. 

 45° E.; 44° S. 48° E. 



There is, so far as I can see, no specific difFerence between 

 the antaz'ctic R. inermis and the boreal R. ohtusa. The former 

 is somewhat coarser and has more visible fulcral ribs of 

 the Zone. 



