RADIOLARIA 



263 



One skeleton; spherical or polyhedral, with an opening (phylom) and with 



radiating spines Legion 4 Phaeocalpia 



Skeleton spherical or polyhedral, with uniformly distributed large rounded 

 pores Family 1 Castanellidae 



Genus Castanidium (Fig. 108, c) 



Skeleton similar to the last, but the base of each radial spine is surrounded 

 by pores Family 2 Circoporidae 



Genus Circoporus (Fig. 108, d) 



Skeleton flask-shaped with one or two groups of spines 



Family 3 Tuscaroridae 



Fig. 108 a. Challenger on wyvillei. X105 (After Haeckel). 



b. Medusetta ansata. X230 (After Borgert). 



c. Castanidium niurrayi. X25 (After Haecker). 



d. Circoporus octahedriis. X65 (After Haeckel). 



e. Tuscarora murrayi. X7 (After Haeckel). 



f. Coelodendrum ramosissimum. X 10 (After Haecker) (From 

 Kiihn). 



Genus Tuscarora (Fig. 108, e) 



Central portion of the skeleton consists of two valves 



Legion 5 Phaeoconchia 



Valves thin, each with a conical process which divides into branched tubes 

 Family 1 Coelodendridae 



Genus Coelodendrum (Fig. 108,/) 



