P. T. CLEVE, NOTES ON SOME ATLANTIC PLANKTON- ORGANISMS. 



Amphihymenium elegans. N. Sp. 

 Plate. V. Fig. 1. 



Anns equal, more than twice as long as broad, 5 — 6-jointed; joints inereasing in 

 breadth towards the blunt ends. Their axis a straight line. Patagium enveloping the 

 arms with the exception of the distal ends. 



Length 0,24; breadth 0,09 milliin. 



Found at 25° N. 52° W. December 1898. Temperature 24,2. Salinity 37, it. Desmo- 

 plankton. 



Anthocyrtium anthemis Hkl.? 



Plate III. Fig. 12. 



As there exists no figure of this species, I ani somewhat uncertain about the iden- 

 tification. I have seen a single specimen only, which was found alive at 63° N. 2° E. 

 (March 1898), where it oecurred together with some species of the tricho-type. The 

 description in FLeckel's Monograph (Chall. Rep. pag. 1273) agrees well with iny specimen, 

 but the dimensions are somewhat dissimilar. On my specimen the cephalis was 0,02 millim. 

 long and broad and thorax 0,05 long, 0,i broad. 



LLeckel's species was found in the abysmal depths of the nothern Pacific. If my 

 specimen really belongs to Hjkckel's species, the occurrence above the deep »Norske 

 Kende» is a fact of considerable interest. 



Challengeron brevispina. N. Sp. 

 Plate III. Fig. 14, 15. 



Shell ovate, scarcely compressed, with a single, very short conical spine on the aboral 

 pole. Peristome with a single truncate tooth of the same length as the aboral spine. 

 Structure: quincuncially disposed alveoli, about 4 in 0,oi millim. 



Length 0,oe; breadth 0,04 millim. 



I found a single specimen only in a sarnple from 63° N. 2° E. (March 1898). 

 Temperature 6,7. Salinity 35, 10. 



Glathrocanium minutum. N. Sp. 



Piate IV. Fig. 9. 



Horn of the cephalis fenestrated. Cephalis hemispherical with small subquadrate 

 pores and a horn of l 1 /-' the length, surrounded by an irregular network. Length of the 

 two joints 3:5; breadth 1:2. Thorax with an irregular network; its ribs united by a 

 circular, irregulary latticed ring. Peristome smooth. 



