388 THE BEGINNINGS OF LIFE. 



The radii are now withdrawn, while the pellicula in 

 which they were encased is retracted and hardened into 

 seta2, with the rest of the pellicula, which now becomes 

 a lifeless transparent cyst. A more delicate cyst is 

 then secreted within this, and the remains of the con- 

 tained protoplasm, having separated itself from the 

 chlorophyll, segments into a group of monociliated 

 Monads, which sooner or later find their way through 

 the cysts into the cell of the Spirogyrathc latter by 

 this time having passed far into dissolution, so that 

 the Monads afterwards easily escape into the water 1 / 

 This was the process seen by Mr. Carter when the cells 

 of Spirogyra were not (as they are just before conju- 

 gating) loaded with starch. But when the changes took 

 place at the period of conjugation they were somewhat 

 different. The whole of the contents of the two con- 

 jugating cells became united into one mass, and having 

 assumed a globular form, remained in this state until 

 the chlorophyll had become more or less brown. After 

 this the protoplasm reappeared at the circumference of 

 the sphere in two forms, viz. in portions which leave the 

 mass altogether after the manner of Amcebas, or else in 

 the form of tubular outgrowths which continue to 

 maintain their connexion with the sphere. In both 

 instances the protoplasm is without chlorophyll, but 

 charged with oil globules; and both forms make their 



1 The dissolution of the filaments is a. slow process of thinning, not 

 putrefactive in nature ; indeed Mr. Carter says : ' Putrefactive decompo- 

 sition at the commencement destroys this process altogether.' 



