Studies of Tissue Growth 



455 



cific amounts of regeneration when calculated by dividing the 

 lengths of new buds by the final disk diameters. The different 

 results shown by columns eight and nine are obvious and empha- 

 size the error of using the final diameters in the calculations instead 

 of the original diameters. The medusse most injured, although 

 in this experiment they are actually regenerating at the fastest 

 rate, are also most rapidly decreasing in size and so give a dispro- 

 portionate divisor in the calculations if their final size is used. 



TABLE VIII 



Tabulated summary of Tables III to VII showing the rates of regeneration and the decrease tn size when 

 Cassiopea xamachana regenerates diferent numbers of oral-arms. The upper half of table shows the 

 conditions after seventeen days, the lower half afte' twenty-four days 



Table VIII is divided into two parts the upper part shows the 

 results of the entire experiment 17 days after the operation. The 

 lower part gives the results shown by the number of individuals 

 indicated 24 days after the operation. 



The facts of chief importance contained in the tables are : the 

 decrease in size of the medusae during the experiments in direct 

 relation to the number of arms being regenerated (Fig. 8), and the 

 absence of any significant relation between the number of regen- 



