IQO E. H. HARPER. 



6. Growth takes place at right angles to a cut surface, and it 

 the cut is oblique the bud will grow out at an angle to the axis 

 of the body. Straightening is affected after the penetration of 

 the lumen of the pharynx into the region, probably under the 

 influence of the tension produced by the peristaltic motions of 

 the intestine. 



7. Sexual individuals lose the power of regeneration to a large 

 extent just as they do their power of budding. In an advanced 

 sexual stage regeneration may fail to occur or be incomplete. 



I wish to express my thanks to Dr. C. M. Child for suggesting 

 to me the subject of this paper and for further suggestions rela- 

 tive to some of the results described. 



HULL ZOOLOGICAL LABORATORY, 



UNIVERSITY OF CHICAGO, 1903. 



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