REPORT ON THE RADIOLARIA. 987 



Subgenus 1. Tncyclarium, Hacckel. 



Definition. — Sagittal ring circular, sraaller than the other two rings, which are both 

 elliptical. 



1. Trissocyclus stauroporus, n. sp. (PI. 83, fig. 5). 



Sagittal ring circular, smaller than the other two equal eUiptical rings. On each of the six 

 corners (or crossing points of every two rings) are developed four small pores, forming a cross 

 around the poles of the three axes. All three rings smooth, without spines. 



Dimcndons. — Height of the frontal ring 0'09, breadth 0-13. 



Habitat. — Central Pacific, Station 265, depth 2900 fathoms. 



2. Trissocyclus triaxonius, n. sp. 



Sagittal ring circular, smaller than the two other equal elliptical rings. From the edges of all 

 three rings are developed small branches, which by irregular ramification and anastomoses form 

 small irregular meshes along the rings. Similar to Trissocircus odostoma, but with thicker rings ; 

 it may be developed from the latter species by connection of the branches which border the rings. 



Dime7isions. — Height of the frontal ring 012, breadth 0-15. 



Habitat. — South Pacific, Station 298, depth 2225 fathoms. 



Subgenus 2. Tricyclonium, Haeckel. 

 Definition. — All three rings equal, circular. 



3. Trissocyclus spTiceridium, n. sp. (PI. 93, fig. 12). 



All three rings equal, circular, thorny ; their rods prismatic, three-sided, with three denticulate 

 edges ; the teeth of the lateral edges become branched, and foi-m by anastomoses of the branches 

 small irregular meshes, which partly protect the eight large open gates. 



Dimensions. — Diameter of the three rings 0'16, thickness 0'012. 



Habitat. — Indian Ocean, BeUigemma, Ceylon (Haeckel), surface. 



Family LI. T y M p A N i D A, Haeckel. 



Parastephida, Haeckel, 1881, ProJromus, p. 446. 



Definition. — St e p h o i d e a with two parallel horizontal rings, an upper mitral and a 

 lower Ijasal ring; both connected by complete or incomplete vertical rings, or by parallel 

 vertical columellse. 



