AMONG SIMPLE SARCODE ORGA.KISMS. 293 



pale glistening homogeneous spherules, there radiate needle- 

 shaped processes like the spines of an Echinus ; and between these 

 are emitted long slender pseudopodia. The spines are composed 

 of silica ; and each forms at its proximal end a disk-like foot. 

 These basal disks constitute by their approximation a nearly 

 closed siliceous capsule, by which the body is surrounded. The 

 bases of the spines appear to be immersed in a soft sarcode- 



Fi?. 13. 



Aeanthocystis turfacea, as seen in optical section through the centre, c, yesicle- 

 like space, from whose central corpuscle fine filaments are seen radiating; 

 b, pseudopodium ; e, proper body-mass, consisting of a granular protoplasm with 

 green and pale corpuscles and enclosing numerous vacuoles ; f, external narrow 

 clear zone ; a, one of the long radiating spines ; d, one of the short spines. 

 (After Greeff.) 



like substance, which would seem also to intervene between the 

 basal plates and the proper body of the Aeanthocystis, which be- 

 comes thus surrounded by an external clear zone. The pseudo- 

 podia possess a firmer axis-filament and a more mobile cortical 

 layer. Grreeff states that he has seen the surface open here 

 and there and allow the exit of strong protoplasm-streams, and 

 again completely close, leaving no evidence of any breach of 

 continuity. Some of these streams surround the spines, and run 

 up and down them like the mobile cortical layer on the axis-fila- 



LTNN. JOUEX. — ZOOLOGY, VOL. XIII. 25 



