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GABRIELE KASS-SIMON 



bowl which contained approximately 8-10 ml. of solution; solutés were dissolved 

 in well water. Animais were transected at 50 % total length. The time of Tentacle 

 Differentiation (TDT) of proximal halves and the Time of Basai Plate DifTerentia- 

 tion (BDT) of distal halves were recorded. (TDT's and BDT's of standard animais 

 (Tables 1 and 6) represent control criteria.) Protocol was taken as above (in Sec- 

 tion II) until death occurred. 



1. Treatment with RNase 



(a) Animais were subjected to 0.5 mg/ml and 1.0 mg/ml RNase 1 without 

 transection. (b) Animais were pretreated for 24 hours, for 5 hours with 0.5 mg/ml 

 RNase, transected in well water, and allowed to regenerate therein. Similarly, 

 animais were subjected to pretreatment with 1.0 mg/ml only. (c) Animais were 

 subjected to 0.5 mg/ml RNase for 10 hours, for 1 hour, for hours prior to transec- 

 tion in RNase and allowed to regenerate in the présence of RNase. (d) Animais 

 were transected in well water and placed in 1.0 mg/ml and 1.5 mg/ml RNase and 

 allowed to regenerate in its présence. 



2. Treatment with Actinomycin C (Bayer) 



(a) Animais were subjected to 2 gamma/ml Actinomycin C 1 without transec- 

 tion. (b) Animais were pretreated with 2 gamma/ml actinomycin for 24 hours prior 

 to transection in well water and allowed to regenerate in its présence, (c) Animais 

 were transected in well water and allowed to begin régénération. Actinomycin 

 treatment was begun at: time of transection, 10 minutes after transection, 30 min- 

 utes after transection, 1 hour, 2 hours, 3 hours, 4 hours, 10 hours, 12 hours and 

 17 hours after transection. Animais were allowed to continue régénération in the 

 présence of actinomycin until death. 



(c) Results 



1. Treatment with RNase 



The results are summarized in Table 1 1. (a) Intact animais subjected to 0.5 mg/ 

 ml are found to die between 56 and 80 hours (N=9); those subjected to 1.0 mg/ml 

 die between 40 and 72 hours (N=8); (treatment was continuous). By 40 hours 

 animais in 1.0 mg/ml had considerably shortened tentacles which were knobby and 

 to some extent frayed at the tips. (b) Pretreatment only resulted in the complète 

 régénération of the animais. In comparison to standard animais, the TDT's are 



1 Fluka, A.G., Buchs (Switzerland), purum 

 1 Sanamycin, Bayer-Leverkusen (Germany) 



