572 



T. H. Morgan and N. M. Stevens. 



each long piece, observations having been made three or four 

 times daily. A figure opposite the middle of a piece indicates 

 a double structure that did not emerge. 



In order to contrast the 

 development of a series of 

 short pieces cut from unal- 

 tered stems, I. e.^ stems w^ith 

 only an oral polyp, one small 

 series of such pieces was 

 observed with the following 

 results (Table VTf*): 



Here the oral ends of the 

 pieces produce polyps, and 

 there are few aboral polyps. 

 It is interesting to note in 

 the third column that some- 

 thing has delayed the de- 

 velopment of the oral ends 

 of two pieces and aboral 

 polyps have developed in- 

 Whether the single case of a double-headed piece in this 



Table VI. 



Stead. 



table (and by inference in other results when the piece is not so 



Table VII. 



short that the tentacle areas of the ends overlap) can also be 

 accounted for in this way, can not be established from the 

 evidence, although it seems not improbable. 



