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



desmo-plankton, some styli-plankton, intermingled with the desmo- 

 plankton, was met with at some points, viz. at 



21°— 19° N. 25° W. (near Cape Verde Islands), 



*4° S. 29° W. (near Fernando Noronha), 



17° S. 35° W. (N.W. of Trinidad), 



26° S. 36° W., 



34° S. 29° W. 



The last named point is situated on the limit of the ant- 

 arctic drift-ice and was reached on the 9*^ of December. Thence 

 the styli-plankton recurred continually to about 30° S. 91° E. 

 (reached on the 9 *^ ofJanuary). Again, from that point a sterile 

 region was met with, that reached to about 23° S. 90° E., where 

 desrao-plankton was found not spai'ingly. The desmo-plankton- 

 contained about the same forms as the Atlantic desmo-plankton. 

 From the last named point to about 11° S. 89° E. the water 

 was practically sterile, but thence to Sumatra the water con- 

 tained desmo-plankton. 



In the following I will report on the plankton that was 

 found between 33° S. 31° W. and 30° S. 91° E., omitting some 

 rarer forms of the desmo-plankton, which occurred intermingled 

 in some samples. The remaining forms are to be classified as 

 styli- and tricho-plankton, and they will be treated of with 

 reference to the natural classes to which they belong. 



Crustacea. 



Of 35 samples examined, one only, from 36° S. 89° E., con- 

 tained some few copepoda, viz. Clausocalanus arcuicornis and 

 Paracalanus joarvus, both common in the styli-plankton of the 

 Atlantic in the northern hemisphere. 



Ciliata. 



Amphorella amphora (Clap. & Lachm.) Jörg. {Tintinnus 

 amphora Cl. & Lachm. Entz., Bütschli, Amphorella am- 

 pliora v. Dad. Tintinnus quadrilineatus Cl. & Lachm. Am- 



