- u- 



Microchemieal examination . The iswre blue pigment which is found in 

 the involucre of the cyanoplasts presents the following reactions; 



With acids it stains red. With alhali it takes on a greenish yellow 

 color. With nicotine (l, p. 356) in dilute solutions it becomes green. It 

 decolorizes easily with oxygenated water and with sulphurous anhydride. It 

 is slightly soluble in cold water and dissolves quickly in warm water, and 

 slightly acidulated water. 



Through the micro chemical examination of the pigment of the cyanoplast 

 one finds present a substance which behaves toward acid, allcali, alkaloids, 

 solvents, and oxidizing substances like anthocyanine. Therefore, we may con- 

 clude that the pigment referred to belongs to anthocyanine and should not be 

 confused with other pigments. 



While it is easy to determine the principal chemical properties of the 

 pigment of the cyanoplast, it is difficult to determine the chemical nature of 

 its involucre. 



On the whole I have tried to find out if the cyanoplast possesses a 

 plasmatic stroma as do the chromatophores and the elaioplast. Such a stroma 

 I was unable to find, although, using many methods of fixation, such as picric 

 acid, chromic acid, acetic acid, absolute alcohol in an aqueous or alcoholic 

 solution of corrosive sublimate, I have not been able to fix and stain it. 

 In all attempts made with the above-named liquids the cyanoplasm dissolves 

 and disappears. 



Verifying the absence of a plasmatic stroma, I tried to determine the 

 nature of the involuofe of the cyanoplast. 



The mode 5neansJ of resistance of the cyanoplast to attack by the 

 several solvents, such a^ water, alcohol, neutral salt solutions, acids and 

 dilute alkalis, and potassium iodide solution, shows that in them it is pos- 

 sible to distinguish a peripheral region which differentiates from the color 

 subsfance by a greater resistance to the action of the determinative solvent. 



