REPORT ON THE RADIOLARIA. 585 



6. Stylotrochus huxleyi, Haeckel. 



Stylospongia huxleyi, Haeckel, 1862, Monogr. d. Radiol., p. 473, Taf. xxviii. fig. 7. 



Spongy framework of the disk in the inner part with five concentric rings, in the outer part 

 quite irregular. Ten marginal spines, conical at the base, about as long as the radius of the disk, 

 without inner piercing prolongations. 



Dimensions. Diameter of the disk O12 ; length of the radial spines - 06, basal breadth 0'003. 



Habitat. Mediterranean (Messina), Haeckel. 



7. Stylotrochus geddesii, n. sp. (PI. 41, fig. 11). 



Stylospongidium geddesii, Haeckel, 1881, Atlas (pi. xli. fig. 11). 



Spongy framework of the disk in the inner part with four to eight concentric rings (or partially 

 spiral convolutions), in the outer part quite irregular. Thirty to fifty pyramidal marginal spines of 

 variable size, one-fourth to one-half as long as the radius of the disk, outer prolongations of inner 

 piercing radial beams, which arise from various concentric rings. I call this interesting species, 

 which is intermediate between Stylodictya and Stylotrochus, in honour of the morphologist 

 Mr. Patrick Geddes of Edinburgh. 



Dimensions. Diameter of the disk 0'15 to 0'25 ; length of the radial spines 0'03 to 0'06, 

 basal breadth 0'004 to O'Ol. 



Habitat. Pacific, central area, Stations 270 to 274, in 2350 to 2925 fathoms. 



Genus 259. Spongotrochus, 1 Haeckel, 1860, Monatsber. d. k. preuss. Akad. 



d. Wiss. Berlin, p. 844. 



Definition. S pongodiscida with numerous solid radial spines (five to ten or 

 more), which are scattered over the whole surface and the margin of the disk, or regularly 

 disposed on both sides of it. 



The genus Spongotrochus differs from the foregoing and nearly allied genus by the 

 distribution of the numerous radial spines. These are not confined to the margin of 

 the disk, but also scattered on its whole surface, and sometimes symmetrically disposed 

 on both its sides in a regular manner. Also in this genus the spongy framework is 

 sometimes quite irregular (Spongotrochiscus}, at other times in the middle part with 

 enclosed concentric rings (Stylospongidium). 



Subgenus 1. Spongotrochiscus, Haeckel, 1862, Monogr. d. Radiol., p. 463. 



Definition. Spongy framework of the whole disk irregular, without concentric 

 rings or spiral convolutions. 



1 Spongotrochus= Spongy wheel ; avoyyn;, rtfxo;. 

 (ZOOL. CHALL. EXP. PART XL. 1885). Er 74 



