KEPORT ON THE RADIOLARIA. 465 



Genus 201. Staurocyclia,^ Haeckel, 1881, Prodromus, p. 458. 



Definition. — Coccod iscida with four solid radial spines on the margin of the 

 disk, crossed in two equatorial diameters perpendicular one to another. Medullary shell 

 simple. 



The genus StaurocycUa is characterised by four radial wpiues on the margin of the 

 disk, which are opposite in pairs and situated in two equatorial diameters, commonly 

 perpendicular one to another. They form therefore a rectangular cross (rarely more 

 or less irregular). The genus corresponds exactly to Staurodicti/a in the family 

 Porodiscida. The medullar}^ shell is simple. 



1. StaurocycUa cniciata, n. sp. (PL 37, fig. 1). 



Phacoid shell two and a half times as broad as the medullary shell, surrounded by six to eiglit 

 regular rings, which are di\-ided liy fifty to se\-enty piercing beams into square chambers. Pores 

 regular, circular ; six on the radius of the phacoid shell, one single pore on each chamber. Four 

 crossed radial spines, arising from the medullary shell by thin Ijases, prolonged over the dentatcd 

 margin as four strong quadrangular swords, as long as the rachus of the (hsk. 



Dimensions. — Diameter of the disk (with eight rings) 0-23, of the phacoid shell 0-09, of tiie 

 medullary shell 0'035. 



Habitat. — Pacific, central area, Station 267, depth 2700 fathoms. 



2. StaurocycUa serrata, u. sj:). 



1 Haliomma sp., Bury, 1862, Polycystins of Barbados, pi. xxii. tig. 2. 



Phacoid shell twice as broad as the medullary shell, siu-rounded by three to four spongy rings, 

 which are divided by thirty to forty radial beams into irregidar chambers. Pores in the phacoid 

 shell regular, circular, five on its radius ; in the chambered spongy girdle much smaller and 

 irregular. Margin dentated, witli four crossed, very large, quadrangular spines, as long as the 

 radius of the disk, with wing-shaped, serrated edges. 



Dimensions. — Diameter of the disk (with four rings) 0-2, of the pliacoid shell O'l, of the 

 medullary shell 0'05. 



Habitat. — Fossil in the rocks of Barbados. 



3. StaurocycUa phacostaurus, n. sp. (PI. 37, figs. 2, 3). 



Phacostaurus pyramidalis, Haeckel, 1879, MS. (as a separate genus). 



Phacoid shell two and a quarter times as broad as the medullary shell, connected with it by 



twelve radial beams (four equatorial and eight divergent) and surrounded by one single ring, which 



is divided by forty radial beams into regular chamljers. Pores regular, honeycomb-like in the 



1 StaurocycUa -.^Cm\\\9.v shell with four crossed spines ; orxv^o;, xi/xAia. 

 (ZOOL. CHALL. EXP. PART XL. — 1885.) Rr 59 



