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CELLS, TISSUES, AND ORGANISMS 



sociated liver-forming cells from 7-day chick embryos coalesced con- 

 sistently into a single spherical or oblong aggregate; neural-retina cells 

 from the same embryo formed a number of aggregates of characteristic 

 shape; mesonephros cells from the same source produced numerous 

 diversely sized cell clusters; cartilage-forming cells from 4-day embryo 



Figure 4. Aggregation patterns of rotation-compounded dissociated cells 

 (24-hour aggregates in standard medium), a. Cell suspension, liver (7-day 

 chick embryo); b. liver aggregate; c. neural-retina aggregates; d. meso- 

 nephrose aggregates; e. limb (4-day embryo) cell aggregates. 



