Life-history 0/ Clatlirulina elegans. 269 



siliceous capsule. The pedicel also becomes inore rig'id, 

 though always retaining a degree of flexibility. This 

 manner of reproduction was first described by Cienkowski, 

 the GTcat Kussian observer and discoverer of Clathrulina 

 elegans (see Leidy's ' Rhizopods of North America ). 



In the second mode of reproduction the rays are not with- 

 drawn, nor does the body divide, but the sarcode becomes 

 finally vacuolate, presenting knob-like projections. Suddenly 

 a small mass of sarcode, usually one of the knob-like projec- 

 tions, detaches itself, and, passing out of the capsule, shoots 

 out rays and develops, though more slowly, in the manner 

 described above. This continues until the parent body is 

 much reduced in size, when the rays again protrude, and the 

 animal returns to its normal condition. 



The third mode of reproduction is by the formation and 

 liberation of minute germs. In this state also the rays are not 

 withdrawn, but the body of the GJathndina becomes finally 

 filled with minute green particles, which, even before libera- 

 tion, exhibit active motion, A number of these are expelled, 

 enclosed in a thin protoplasmic film or globular sac, which 

 bursts shortly, and the liberated germs swim away. The 

 development of these germs after this point is yet to be 

 followed. 



The fourth mode is still more remarkable, and is also 

 significant in bringing to light a new phase in the life- 

 history of the Ileliozoa. The Clnthridi)ia in which tliese 

 phenomena were first observed withdrew its rays and divided 

 into four parts, as in the ordinary method ; but the sarcode^ 

 instead of becoming granular and of a rough surface, grew 

 smoother and more transparent. Then followed a period of 

 quiescence — in this case of five or six hour's duration, 

 although in other instances lasting three days and nights ; 

 after wdiich one of the four parts began slowly to emerge from 

 the capsule, a second following a iQ\s moments later. 



While passing through the capsule, these masses of sar- 

 code seemed to be of a thicker consistence than the simihir 

 bodies which, in the ordinary methods, instantly assume the 

 Actino])hrys form. After both had passed completely through 

 for nearly a minute they lay quiet, gradually elongating 

 meanwhile. Then a tremor became visible at one end, and a 

 short prolongation of the sarcode appeared waving to and fro. 

 This elongated at the same time into a flagelluui, the vibra- 

 tions becoming more rapid, until at the same moment both the 

 liberated monads darted away througli the water. They were 

 followed for about ten minutes, when both were lost to sight 

 among a mass of sediment, and the fear of mistaking cue uf 



