RADIOLARIA — ZVCtOCIRCDS, ZYGOSTAURUS 199 



ZYGOCIRCUS PRODUCTUS (R. Hertwig.) 



(LithociiTus prod. Hertw. Organism, d. Radiol. PI. VII fig. t.) 



1898 February: 34° N. 78^ W. 

 Marvh : 12^ N. hi" W. 

 May: 41° N. 51° W. 

 September: 25-— 33° N. 74° W. 

 October: 26° N. 76" W. 



Temperature: 24.s, mean of 6 obs., max. 28, min. 19. 

 Salinity: 36.is, mean of 4 obs., max. 36.3o, min. 36.oi. 

 Plankton-type. Found in the Atlantic, Mediterranean and 

 Pacific. — 1). 



ZYGOCIRCUS RHOMBICUS Hkl. 



(Chall. pag. 946.) 



1898 Febi'iiary: llr N. 71° W 



Temperature: 20.?. 



Plankton-type. Found in the south Atlantic. — 1). V S. ? 



ZYGOCIRCUS TRIQUETRUS Hkl. 



(Chall. pag. 947 PI. 81 fig. 3.) 



1898 February: 16 °N. 71° W 



Temperature: 20.?. 



Plankton-type. Found in the Atlantic, Mediterranean and Pa- 

 cific. — 1) ? S. ':> 



ZYGOSTAURUS SAGITTALIS Hkl. 



(Chall. pag. 775 PL CXXXI fig. 8.) 



1897 December: Vt N. 50' W. 

 February: 26° N. 74° \K. 

 March: 23° N. 28° W 



Temperature: 23.?, mean of 3 obs., max. 26.6, min. 20 9. 



Salinity: 36. 91 (one obs.). 



Plankton-type. Found in the central Pacific. — D. 



