NOTES ON REGULATION IN STYLARIA LACUSTRIS. 



187 



The regeneration of the anal segment is equally slow in the 

 advanced sexual forms and the part regenerated is not of full 

 size (Fig. 16). 



3. In a single instance the clitellum was regenerated, but the 

 specimen was unfortunately not kept under observation long 



II a. 



ii b. 



II c. 



II d. 



II e. 



~) 



\ 



I2,f. 



12 b. 



12 a. 



14 a. 



\ / 



14 b. 



