C. M. CHILD. 



SERIES 56. 



December 15, 1902. Disc, tentacles and oesophageal region 

 were removed from ten large specimens by a transverse cut ab- 

 oral to end of oesophagus. The aboral piece was then cut into 

 two pieces, A and B, of equal length (Fig. 7) which 

 were kept for comparison. 



December 19 : four days after section : 



A. Nine pieces with ends closed ; a few dis- 

 tended, the others partly filled with water ; one 

 piece still collapsed. 



B. All still collapsed. 



December 22 ; seven days after section : 



A. All distended ; ends well expanded, showing 

 new tissues in a few pieces the tentacular ridge is 

 just appearing. 



B. All still collapsed. 



December 26 : Eleven days after section : 

 A. Tentacular ridge distinct, with faded pig- 

 ment ; in a few pieces the first traces of marginal 

 tentacles distinct. 



B. Filling with water but not distended ; new tissue at oral 

 end not visible. 



December 28 : Three days after section : 



A. Marginal tentacles 0.5 mm. 



B. Four pieces fairly well filled with water ; tentacular ridge 

 just visible ; six pieces collapsed or only partly filled ; tentacular 

 ridge not visible. 



January 3, 1903 : Seventeen days after section : 



A. Marginal tentacles 2-3 mm. 



B. One piece distended ; marginal tentacles 2 mm. Nine 

 pieces partly or completely collapsed ; no tentacular ridge or 

 tentacles visible. 



Circumstances necessitated the conclusion of the series at this 

 time, so that it was impossible to determine whether the nine 

 pieces of B would ever have regenerated. The series affords, 

 however, some interesting results. As in all other series regen- 

 eration is much less rapid in the aboral pieces ; in only one case 

 did the aboral pieces regenerate tentacles before the conclusion 



