34 THÉEL, HERMAPHRODISM IN HOLOTHURIDS. 



It is a striking fact that not all the eggs in such tubes 

 whicli are attacked by these migratory cells are destroyed. 

 Some of them at least are evidently capable of resisting the 

 destroying work for a longer time. 



Special attention shoidd be paid to the fact that the two 

 kinds of phagocytes perforra somewhat different work, the 

 one devouring eggs, the other attacking superfluous tissues 

 and organsystems. 



