-* 7 ^ 

 Later, retaining their spherical form, they increase in size and soon 

 assume a more intense color, attaining in complete developnent dimensions 

 relatively greater (PI. XVII, fig. 2). 



In this period of their evolution the cyanoplasts indicate marked 

 modifications, in so much that they lose their globose form, assviming odd, 

 extremely variable shapes (PI. XVII, fig. 3), and reveal at the same time a 

 very delicate membranous involucre, within which there is found included the 

 colored substance. This occurs in the form of a central globule of con- 

 siderable size or many spherical or oval corpuscles of variable size, which 

 may be found indefinitely distributed withia|the involucre or else borne 

 toward the extremity of the prolongation vdxich occurs in this stage. The 

 number of such corpuscles varies according to the dimensions of the cgranoplast. 

 This latter, moreover, assumes a form and dimensions which are extremely vari- 

 able, and permits the supposition that they become fragmented. In fact, many 

 cyanoplasts are more or less thin in the median part and. the two or three 

 swollen extremities are somewhat far apart. It is not even improbable that 

 there sometimes follows a mult idivis ion, since one finds in the cytoplasm some 

 tiny rotund colored bodies which are also azure blue and which probably repre- 

 sent the daughter cyanoplasts cut off from the mass of the adult cyanoplast, 

 but in this regard my observations are incomplete. I could not follow this 

 multiplication. Eather would I believe ^hat the extremely variable form which 

 the cyanoplasts taJlae in this stage of their evolution is due to phenomena of 

 degeneration and at the same time that the other bodies (cojrpicciuoli) to 

 which I have referred represent young cyanoplasts formed by neoformation from 

 the plrotoplast. 



The fact remains that from the beginning in each cell one finds con- 

 stantly a single cyanoplast which on becoming adult is accompanied by other 

 sp^l^ical bodies of light color and of smaller dimensions. 



