576 



GABRIELE KASS-SIMON 



Table 4. 



FTN — ITN ( Final Tentacle Number minus Initial Tentacle Nwnber). Mean différences 

 between number of tentaeles at final and initial tentacle counts in each of four clones of 

 standard animais at the various axial levels. Values omitted from statistical considération 

 are in brackets. JBT=Just Below Tentaeles. N= Number of Regenerated Animais. 





Clone 7a Ç 



Clone 6 ? 



Clone 18 <? 



Clone 3a ? 



JBT 



"NT — 



2.54 ± 1.35 



1.92 ± 1.04 



1.80 ± 1.15 

 10 



2.00 ± 0.88 

 14 



75% 



N = 



1.89 ± 1.66 

 18 



0.94 ± 1.21 

 16 



1.92 ± 1.35 

 12 



2.30 ± 1.88 

 10 



50% 



N= 



1.95 ± 1.76 

 21 



1.38 ± 1.61 

 13 



1.23 ± 0.95 

 13 



1.92 dz 1.14 

 12 



25% 



N = 



1.21 ± 1.16 

 15 



1.50 ± 1.00 

 8 



0.40 4- 0.68 

 10 



0.86 ± 0.83 

 8 



10% 



N = 



(0.66 ± 0.06) 



3 



1.40 ± 1.25 

 7 



(0.25 ± 0.05) 

 4 



(0.50 ± 1.00) 

 4 



tentacle increase. Further, thèse data are already included in the FTN — ITN 

 évaluation, where absolute increase in tentacle number is considered. For each 

 clone, none of the différences among the four levels proved to be significant. The 

 data are pooled and the weighted means shown in Figure 4 and it is évident that 

 no steadily declining gradient exists for this factor. 



6. Time of Basai Plate Differentiation (BDT) 



The data are given in Table 6 and summarized in Figure 5. (See also Figure 6.) 

 A comparison of ail six levels in each clone reveals a différence significant at 0.1 % 

 level (Clone 7a ?: F=30.8; Clone 6 ?: F=5.17; Clone 18 S- F=61.8; Clone 3a ?: 

 437). However, when JAB and JBT were omitted from statistical analysis and 

 only 75 %, 50%, 25 % and 10% levels were compared, no significant différence was 

 found in three clones and only a significance at 5 % found for Clone 7a $ (F=9.8). 

 This différence, however, is not to be weighted too heavily, in view of the data 

 from the other clones. In any case, a clear-cut gradient was not demonstrable as 

 can be seen from Figure 5. The number of animais failing to regenerate at JBT in 

 the allotted time is significantly higher than those of any of the other four levels. 



