AMONG SIMPLE SAHOODE ORG ANTSlStS. 



289 



If these characters be borne iu mind, we shall have no diffi- 

 culty in determining how far the freshwater organisms now about 

 to be mentioned admit of a comparison with the true Eadiolaria. 



Among these freshwater Rhizopods the form which eoraes nearest 

 to Actinophrys and Actinosphcerium, and hence to the typical He- 

 liozoa, is that of Cilioplirys (fig. 11) . Under this name Cienkowsiii 

 has described a new genus of heliozoal Rhizopods, represented 

 by a single species, G. infmiormm, which he finds common in the 

 scum of long-standing infusions, and on which he made some 

 important observations, showing that the swarm-spore enters into 

 its development-cycle*. It is thus, if we except a fragmentary 

 observation by Archer on what he regards as a large green variety 



Ciliophrys infusionum. A, the Ciliophri/s in its developed condition ; y, con- 

 tractile vacuoles ; n, nucleus. B, the swarm-spore into which the Ciliophrys has 

 become converted. C, the Ciliophrys in the act of self-division; each half 

 has become converted into a swarm-spore. D, the two swarm -spores of 

 becoming fused into one another. E, the fusion further advanced. (After 

 CienkowsM.) 



* " Ueber einige Rhizopoden und verwandte Organismen," Arch, fur mikr. 

 Anat. vol. xii. 1876. 



