36 THE PSYCHIC LIFE 



These little bodies, which in the vegetables are called 

 leuciies, have a granular and reticulate structure; they 

 are impregnated with a coloring substance, at times 

 green, at times yellow, and at times brown, as the case 

 may be; in fact, several coloring substances are 

 present, which, by intermixture in different propor- 

 tions, form colors of many varieties. The best known, 

 after green chlorophyl, is yellow chlorophyl or diato- 

 inin. The latter coloring substance can be absorbed 

 by alcohol. 



The Euglenoididse, the Chlamydomonadidae, and 

 the Volvocinse exhibit enormous chromatophores. In 

 the case of the Euglena;, the chromatophores are 

 formed of small discoid plates; they are situated di- 

 rectly under the cuticle, so that the light can act 

 upon them (see fig. 4). In certain species of Flagel- 

 lata, they are exhibited under the cuticle in the form 

 of two large plales which envelop the protoplasm 

 like a cuirass formed of two pieces. The Chlamydo- 

 monadidae and the Volvocinse have green chromato- 

 phores, disc-shaped, and very small. 



In the centre of the chromatophore a small bright 

 space is observed which was formerly thought to 

 be filled with chlorophyl; in reality, it is a minute solid 

 globule which shows an extremely close analogy with 

 the substance composing nuclei, or nuclein. It ex- 

 hibits the same chemical reactions; it actively absorbs 

 coloring matter and grows extremely brilliant when 

 treated with acids. Schmitz gives this little body the 

 name of pyrenoid (from 5ri'p;>, nucleus). It is around 

 the pyrenoid, and probably through its action, that 

 starch forms; it is deposited in grains or re-unites in a 

 ring about the pyrenoid, a fact easily ascertained by 

 coloring them with iodine. 



