418 PHOF. ALLMAN OK THE UECEI^^T KKSKAKCHES 



encysted for a certain time, the contents of the capsule become 

 broken up into numerous separate masses of protoplasm, which 

 finally escape in the form of the spindle-shaped zoospores found 



in the Nitella. 



Fig. 10. 



Vrotomonas Huxleyi. 

 A, fragment of a cylindrical diatom (Rhizosolenia) to which the Frotomonas, 

 B, in its encysted state, is attached. C, the cyst with its contents broken up into 

 spherical non-nucleated protoplasm masses. E, the spherical masses, after having 

 developed a flagellum, have become free swarm-spores by the rupture of the cyst. 

 D, amoeboid condition assumed by the swarm-spore. F, the amoeboid swarm- 

 spore having assumed the form of an Actimphrys by the emission of numerous 

 fine pseudopodia. (After Haeckel.) 



The generic name of Monas, under which Cienkowski has de- 

 scribed this singular organism, has been changed by Haeckel* 

 into that ofPro^owow«s, on the very tenable ground that the name 

 oi Monas had been long applied to a group of microscopic orga- 

 nisms which we should not be justified in confounding with the 

 monads of Cienkowski. Haeckel has, moreover, described another 

 representative of the genus, which he found in the Canary Islands 

 attached to the surface of a floating diatom, and which he names 

 Frotomonas Knxleyl He gives a very complete account of its 

 life-history, which is in all essential points like that of P. amyli. 

 * Monographic der Moneren. 



