IV. 



THE PHASES OF DEVELOPMENT OF 

 LIVING MATTER.* 



THIS article is a translation of a publication in German in 

 1873. What at that time were considered to be phases of 

 life of the protoplasm, must to-day be taken as different phases 

 in the development of living matter, one of which is its retic- 

 ular arrangement in protoplasm. This latter term, then, in the 

 present view, is applicable to only one of the phases of devel- 

 opment. 



Amcebce. In specimens taken from an infusion on the third or 

 fourth day after its preparation, we meet with a few lumps of 

 protoplasm, not over 0.008 mm. in size, in slow locomotion. These 

 lumps are shining, yellowish, and formed by a very dense reticu- 

 lum of living matter j some of them contain vacuoles. A nucleus 

 is not recognizable in such a youthful amoeba. A few days later 

 on, besides amoebae of the described size, others are found which 

 are larger, finely granular, and execute lively changes of shape 

 and locomotion. Every one of these amoebae has a pale gray, 

 homogeneous nucleus. 



Specimens taken from the infusion in the third or fourth 

 week contain, in addition to younger forms, many amoebae, with a 

 varying number of coarse, shining, yellowish granules. These are 



* Untersuchungen iiber das Protoplasma. III. Die Lebensphasen des 

 Protoplasmas. Sitzungsber. der Akademie der Wissensch. in Wien. June, 



1873. 



