REPORT ON THE RADIOLARIA. 



59 



Surface of the spherical 

 shell smooth, rough, or 

 thorny, but not armed 

 with radial spines. 



Surface of the spherical 

 shell armed with two, 

 four, or six radial main 

 spines, opposite in pairs - 

 in one, two, or three 

 dimensive axes (always 

 solitary). 



Synopsis of the Families of Sphaeroidea. 



, T . , ., f Spherical shell commonly 



A. Liosphaerida monozoa. J 



c,. , r , , , . , , quite regular, simple, or 



Single ce ls(each withshell) \ LnvS ,,f }. 

 living solitary. 



composed of two ormore 

 concentric spheres, 



5. LIOSPH&BIDA. 



B. Liosphzerida polyzoa. Ag- 

 gregated cells (each with 

 shell) living in colonies. 



Spherical shell commonly 

 more or less irregular, 

 simple (rarely composed 

 of two concentric 

 spheres), 



6. COLLOSPH^ERIDA. 



Two radial main-spines, opposite in one axis of the shell, . 7. STYLOSPH.ERIDA. 



Four radial main-spines, opposite in pairs in two dimensive 

 axes, perpendicular one to another, 



Six radial main-spines, opposite in pairs in three dimensive 

 axes (perpendicular one to another), 



8. STAUROSPH.ERIDA. 



9. CuBOSPHjERIDA. 



Surface of the spherical shell covered with numerous (commonly irregularly disposed) 

 radial spines, often also twelve to twenty, more or less regularly disposed, 



10. ASTROSPH-aSRIDA. 



Family V. LIOSPHAERIDA, Haeckel, 1881. 



Liosphcerida, Haeckel, 1881, Prodromus, p. 449. 



Definition. S phaeroidea without radial spines on the surface of the spherical 

 shell ; living solitary (not associated in colonies). 



The family Liosphserida comprises all those solitary Sphasroidea in which 

 the surface of the spherical shell is not armed with radial spines. Nearly the half of this 

 large group is formed by the EthmosphaBiida, in which the carapace is a quite simple, 

 spherical lattice-shell ; this subfamily is probably the common ancestral group from 

 which all other S p h a3 r o i d e a, or even all Sphserellaria, can be derived in a 

 phylogenetical as well as in a morphological sense. The central capsule in this first sub- 

 family is constantly enclosed by the fenestrated shell, and separated from it by the 

 jelly-veil. The shell is therefore an extracapsular or medullary shell. 



To these simple Ethmosphserida all other subfamilies can be opposed as " Lio- 

 sphasrida concentrica," as their carapace is composed of two or more concentric lattice- 

 shells ; two in the Carposphaarida, three in the Thecosphaarida, four in the Cromyo- 

 sphserida, five or more in the Caryosphserida. In all these four subfamilies the 

 concentric shells are simple (not spongy) fenestrated shells. In a sixth subfamily, in 

 the Plegmosphserida, the shell is wholly or partially composed of spongy wicker-work, 

 with or without a latticed medullary shell in the centre. 



The internal radial beams, in the " Liosphserida composita " connecting the 

 concentric spheres, exhibit in their number and disposition similar important 

 differences, such as the external radial spines in the Astrosphserida, The following eight 



