REPORT ON THE RADIOLARIA. 



209 



Synopsis of the Genera of Astrosphcerida continued. 



VI. Subfamily 



Spongiommida. 



(Spherical shell whole or 

 partly spongy, with or " 

 without enclosed latticed 

 medullary shells in the 

 centre. ) 



Subfamily COSCINOMMIDA, Haeckel. 



ffeliosphcerida, Haeckel, 1881, Prodromus, pp. 449, 450. 

 Definition. A strosphserida with one single spherical lattice-shell. 



Genus 88. Acanthosphcera, 1 Ehrenberg, 1858, Monatsber. d. k. preuss. Akad. d. 



Wiss. Berlin, p. 12. 



Definition. A strosphaerida with one simple lattice-sphere, covered with 

 simple radial spines of the same kind. 



The genus Acanthosphcera exhibits the most simple form of all Astrosphaerida ; a 

 simple spherical lattice-shell, the surface of which is covered by radial spines of one and 

 the same kind. The number of the latter is very variable, often twelve to twenty, 

 regularly disposed ; in other cases forty to sixty or more ; and sometimes at each nodal - 

 point of the network a spine is developed. 



1 Acanthosphasm = Spiny sphere ; af*av0, 

 (ZOOL. CHALL. KXP. PART XL. 1885). 



Rr27 



