SEARS CROWELL 



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In a day or two in Coidijloplwra and other athecate forms a small 

 bud (sometimes several) appears on the upper side of the cellular 

 ball and quickly develops four or so tentacles. If fed, it will grow. 

 In Campaniihha, a growth zone appears on the ball and produces 

 either a stolon or a pedicel. This grows out for several days using 

 the materials in the ball. Finally, after about a week, in exactly 

 the same sequence as in ordinary hydranth development, a new 

 small but complete hydranth is produced. Figure 7 shows sketches 

 of this for Campanularia. 



Fig. 7. Sketches of the production of hydranths from dissociated tissues 

 of Campanularia. At the top are clumps of cells which have been pushed 

 together. Within a few hours these rearrange themselves into a hollow 

 ball. This ball may produce a hydranth in either of two ways: at the left, 

 by the production of a stolon from which a pedicel and then a hydranth 

 develops; at the right, by the production of a pedicel at the top of which 

 a hydranth develops (From Hartman, ref. 9). 



