REGENERATION IN HYDRA ATTENUATA 



583 



The final and Initial Tentacle Numbers at each level are comparable for budding 

 and non-budding animais. FTN' — ITN's for budding animais at each level appear 

 to be higher than for non-budding controls, although the différence did not prove 

 significant. The same holds true for TRF values. Thus, with the possible exception 

 of TDT's at 50%, the régénération performance of budding animais is comparable 

 to or better than non-budding animais. 



Table 7. 



Comparison of Hydranth Régénération at Three Axial Levels of Budding and Non- 

 Budding .Standard" Animais. TDT=Time of Tentacle Differentiation (in hours). FTN= 

 Final Tentacle Number. ITN= Initial Tentacle Number. FTN=ITN= Final Tentacle 

 Number minus Initial Tentacle Number. TRF ^Tentacle Régénération Factor. JBT=Just 

 Below Tentacles. N= Number of Regenerated Animais. 





TDT 



FTN 



ITN 



FTN— ITN 



TRF 





25.14 ± 2.83 



5.14 ± 1.36 



2.38 ± 1.26 



3.00 -b 1.61 



229 -j- 59.8 



Ruddini? 













Animais 













N= 



8 



7 



8 



7 



6 



JBT 













Non- 



28.19 ± 7.96 



4.86 ± 1.30 



2.50 ± 0.96 



2.15 ± 0.78 



119 ± 118 



Budding 













Animais 













N= 



21 



21 



20 



20 



17 





29.79 ± 3.90 



4.86 ± 1.22 



2.86 ± 1.25 



2.00 ± 2.1 



173 ± 104 



Budding 













Animais 













N = 



7 



7 



7 



7 



6 



75% 













Non- 



34.00 ± 6.48 



4.67 ± 1.50 



2.86 ± 0.78 



1.87 ± 1.47 



235 ± 114 



Budding 













Animais 













N = 



16 



15 



16 



15 



8 





52.80 ± 40.50 



5.38 ± 0.99 



2.22 ± 1.11 



3.25 ± 1.60 



273 ± 73 



Budding 













Animais 













N = 



12 



8 



9 



8 



8 



50% 













Non- 



34.35 ± 10.00 



4.59 ± 0.96 



2.71 ± 0.93 



1.88 ± 1.39 



218 ±96 



Budding 













Animais 













N= 



17 



17 



17 



17 



11 



If, now, the TRF's at each level of budding animais are compared among 

 themselves, a différence, significant at 0.1 % is revealed (F= 11.37). No différence 



