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CELLS, TISSUES, AND ORGANISMS 



Figure 1. A cell suspension of 7-day chick embryo neural-retina. 













Figure 2. The initial phase of aggregation in a gyrating flask. There is an 

 accumulation of cells and intercellular materials in the vortex of the liquid 

 culture medium. 



These masses increase in compactness and soon form cell aggregates. 

 By means of this simple procedure, the settling down of cells prior to 

 aggregation is practically eliminated, while their clustering is greatly 

 expedited. Cells of various origins and kinds can be rapidly co-aggre- 



