INTRODUCTION. 



wall is seen almost immediately to slip free from the protoplasmic 

 contents, often with a sudden jerk, and by this action may be 

 removed to some distance from the now naked spore, while it 

 retains its original form as an empty transparent sac.* 



The naked spore remains from six to nine hours without any 

 apparent alteration; at the end of this time a slow amoeboid 

 change of outline is observed, sometimes accompanied by the 

 projection of numerous pointed pseudopodia, and a constriction 

 begins to appear in the middle portion. As this continues, a 

 second constriction can be noticed in each half. The first division 

 may now become complete, but usually the whole of the spore 



contents remains united 

 until a further constric- 

 tion takes place in each 

 quarter, and in about 

 an hour from the time 

 when the first movement 

 was observed the origi- 

 nal ellipsoid body is 

 divided into eight spher- 

 ical portions. These 

 occasionally become free 

 at this stage, but as a 

 rule they continue at- 

 tached to one another by 

 narrow bridges ; a few 

 minutes later each pro- 

 trudes' a flagellum, and 

 assumes the pyriform 

 figure of a swarm-cell; 

 then by the united lash- 

 ing movement of their 

 flagella the cluster of 

 eight swarm-cell's swims 

 away. Theymayremain 

 connected for an hour 

 or more, but eventually 

 become detached, and 

 resemble in all respects 

 the swarm-cells of the 

 Endosporem. , 

 The, Plasmodium. — The phenomena which are met with in the 

 swarm-cell may be seen in the plasmodium on an extended scale. 

 Like the amoeboid phase of the former, it is endowed with power 

 of locomotion, and advances over the substratum with a creeping 

 movement. The interior substance consists of granular proto- 



* I have not observed the emergence of the spore-contents in an amoeboid 

 form through an operzng of the spore-wall as described by Famintziu and 

 Woronin, " Ueber Oe^atium, hydnoides, Mem. Acad. Petersbourg " xx 3 

 1873, ■ ' 



Fia. 4. — Ceeatiomyxa mucida Schroet. 



a. Spore. 



&. Spore-contents escaping from the spore-wall, 

 c to g. Successive stages in the division of the naked 

 spore, to eight. 

 h. Cluster of eight swarm-cells. 

 Magnified 1200 times. 



