GERM CELLS IN THE ARTHROPODA 169 



merits with oxygen and carbonic acid gas indicate 

 that a greater amount of Ectosomen occur when the 

 egg is developed in the latter, as shown by Fig. 49, I, 

 which is from an egg of Cyclops viridis placed one 

 hour after deposition into carbonic acid gas for one 

 hour. 



When various stains were used it was found that 

 the Ectosomen became colored much like the 

 cytoplasm. For example, when stained in methylene 

 blue followed by eosin the chromosomes were blue 

 and the Ectosomen and cytoplasm red, and when 

 stained by the methyl green-f uchsin-orange G method 

 of Heidenhain the chromosomes were green and 

 the cytoplasm and Ectosomen red. 



Amma also attempts to explain the fact that the 

 Ectosomen appear at only one end of the first cleav- 

 age spindle and in only one of the cleavage cells 

 until the two primordial germ cells are formed. 

 He rejects the hypothesis Haecker advanced that the 

 centrosomes possess an unequal influence upon the 

 Ectosomen and that one centrosome attracts all of 

 them because it is stronger than the other, and is 

 inclined to favor the idea that the Ectosomen are the 

 visible evidence of an organ-forming substance which 

 is thus distinguished from the rest of the cytoplasm 

 as ''Kornchenplasma." ^ 



Fuchs (1913) has confirmed for Cyclops viridis 



^ Amma's statement is, "dass im Zellplasma des noch ungefurchten 

 Copepodeneies ein vom ubrigen Eiplasma qualitativ verschiedenes Korn- 

 chenplasma existiert, welches die organbildende Substanz, die Anlagesuh- 

 stanzfur die Geschlechtsorgane darstellt" (p. 564). 



