3. Grube clearly saw how in the stage of the four 

 blastomeres, from the animal side, very small globules of 

 division began to separate; i.e. he established the fact 

 of the formation of micromeres, which are composed mainly 

 of protoplasm, and macromeres, which are rich in yolk. 



4. Later he established that the number of micromeres 

 increased either by separation from macromeres, or by 

 means of multiplication of the early formed micromeres. 



5. By Grube' s observations, the "rudiment" which is 

 formed on the animal pole, owing to the multiplication of 

 micromeres, spreads over the surface of the ovum, as a 

 result of which the macromeres appear inside the embryo. 

 This phenomenon very nearly resembles epibolic gastrulation. 



6. At the end, Grube described the embryonic stripes 

 coming out from three pairs of terminal cells; i.e. he 

 discovered in the annulated worms the phenomenon of 

 teloblastic development. 



7. The embryonic stripes, in Grube' s observations, 

 are displaced towards each other and are united on the 

 ventral side. From the material of the embryonic stripes 

 ("the abdominal shafts") the wall of the worm's body- 

 tegmens, muscles, and nervous system is formed. 



Grube 's excellent work was forgotten, and superiority 

 in the study of the embryology of annulated worms, in 

 particular the leeches, was accorded to Rathke, whose work 

 was published eighteen years later. Rathke 's work without 

 doubt has merit, but also has many defects, so that it 

 can be seen as a step backwards in comparison with the work 

 of Grube. Thus in the maxillary leech Nephelis vulgaris 

 Rathke clearly saw the formation of micromeres, which in 

 Clepsine complanata he did not see, and instead of the 

 micromeres only granularity is illustrated in his drawing 

 in the animal parts of the blastomeres. At a later stage it 

 is shown as if the unlacing of the micromeres has begun, but 

 he did not see whether this led them to division. Together 

 with this, Rathke reproached Grube for seeking the source 

 of micromeres CWANDUNGSBALLEN) in the depths of the 

 globules of the division, while Rathke himself in general 



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