KONGL. SV. VET. AKADEMIENS HANDLINGAK. BAND. 34. N:U I. 11 



Sethoconus criiiitus. N. Sp. 



riato III. Fis. 13. 



Cephalis subsphfi'lciil l;iri;e, with miiuerous In'istlc-.sli.'iprd horns jiiid tdosu polygonal 

 ineslic'S of different size. Collar constriction deep. Tliui-ax conical, with straight outline, 

 gradually increasing in breadth towards the wide open month. I'orcs of the thorax siniihir 

 to those of the cephalis, polygonal and of different size, much broader than tlie thread- 

 like bars. 



Cephalis 0,03 long and broad. Thorax O,ori long and broad. Collar constriction 

 0,02 millim. 



Sparingly along the N. coast of S. America and in the Florida current, 7 -ll'N. 

 53^ 75' W. Temperature 22,4 to 28. Salinity 83,88 to 36,56. 



Sethocyrtis pyrum. N. Sp. 



Plate IV. Fit;. 6. 



Shell thick-walled, pear-shaped, with slight collar stricture. Length of the two 



joints 1 : ti, breadth 1 : 4. Cephalis hemispherical, with a, small horn of half the length 



and unequal small pores. Thorax inflated, with circular, regular pores, quincuncially 



arranged and as broad as the bars. On the nodal points short spines arise. Mouth flat, 

 half as broad as the thorax. 



Cephalis 0,oi2 long, 0,o2 broad. Thorax 0,072 long and U,08 millim. broad. 



Very rare at 45 N. 49 W. (January 1899). Temperature 12. Salinity 35,54. 



Spermatogonia antiqua Leud. Fortm. 

 Plate III. Fie. 17, 18. 



Dr. Leudugeu Fortmorel described in 1(S92 (Diatomees de la Malaisie. Annales du 

 Jardin botan. de Buitenzorg. Vol. XI pag. 49. PI. IV, fig. 8) under the above name an 

 organism from the Malay Archipelago, which he considered as a diatom. The figure has 

 been reproduced in Vax Heurck's Treatise on the diatomacee (1896) pag. 541 with the 

 remark ns it a diatom?. This form is by no means rare in the tropical xAtlantic and 

 cannot be a diatom. It is a part of an organism, of which I have however seen oidy 

 alcohol-preserved specimens. The neadles, called Spermatogonia, are by their arrow- head 

 like ends fastened in groups on a lij'aline sack, which encloses, besides a number of 

 smaller granules, a larger cucumber-like body. This body, which treated with soda shows 

 a peculiar structure of longitudinal and transverse lines, reminds of the central capsule 

 of the radiolarians. If so, the hyaline sack should correspond to the calyrana. But, on 

 the other hand, there is no radiolaria known, wich otters any distant relation to 

 Spermatogonia. From tlie jJieeodarian it difters by the entii-ely dift'erent central capsule. 

 In all cases this form is no diatom, and, if a radiolaria, it belongs to a quite new type. 



