320 MENSCH. 



EXPLANATION OF PLATE XIII. 



Fig. I. Autolytus varians. Parent stock with a chain of five distinct 

 stolons. X 5. 



Fig. I. a. Enlarged parapodium of the parent stock. 



Fig. I. b. Enlarged setae of the parent stock. 



Fig. 2. Enlarged head of the parent stock, x 15. 



Fig. 3. Mature male stolon. X 30. 



Fig. 4. Parapodium of the mature male stolon. 



Fig. 5. Mature female stolon, x 30. 



Fig. 6. Chain of six distinct male stolons. X 18. 



Fig. 7. Very young isolated stolon. 



Fig. 8. Lateral view of the posterior part of stolon i and the anterior part 

 of stolon 2. X 40. 



Fig. 9. Ventral view of the adjacent parts of stolons 2 and 3. 



Fig. 10. Parapodia of stolon 4. 



Fig. II. Lateral view of the posterior part of stolon 3 and anterior part of 

 stolon 4. X 40. 



Fig. 12. Parapodia of stolon 5. 



Fig. 13. Parapodium of a mature female stolon. 



Fig. 14. Longitudinal median section through the head of a mature male 

 stolon. X 140. 



Fig. 15. Transverse section through the last segment of the parent stock in 

 the region of a parapodia. X 200. 



Fig. 16. Transverse section through the posterior part of the last segment of 

 the parent stock, x 200. 



Fig. 17. Longitudinal median section through segment 35, the embryonic 

 region, and the anterior part of the stolon i, Fig. 6. x 175. 



Fig. 18. Transverse section through the anterior segment of the embryonic 

 region of the chain. X 200. 



Fig. 19. Posterior part of a specimen shovring the formation of new segments 

 between segments of the parent stock. X 18. 



