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ZOOLOGY 



No nephridium has been described iu Plumatella; in an 

 allied form, Cristatella, a pair of ciliated tubes are, however, 

 said to lead from the body-cavity and to open by a common 

 pore between the anus and brain. The interpretation of these 



Fig. 115.— View of right half of Pluma- 

 tella fungosa, slightly diagrammatic. 

 After AUman and Nitsche. 



1. Lophophore. 



2. Mouth. 



3. Epistome. 



4. Anus. 



5. Nerve ganglion. 



7. Stomach. 



8. Rectum. 



9. Edge of fold of body-wall. 



10. Wall of tube. Ectooyst. 



11. Parieto-vaginal muscles. 



12. Funiculus. 



13. Body-wall. Endocyst. 



14. Testis. 



15. Testis more mature. 



16. Statoblast. 



17. Ovary. 



18. Spermatozoa free in body-cavity. 



19. Calyx. 



20. Retractor muscle. 



ducts is a subject of uncertainty. The functions of a renal 

 apparatus may possibly be delegated to those large cells in the 

 stomach in which brown granules accumulate during the life 

 of the polypide. 



Plumatella is hermaphrodite. The ova develope from the 

 cells which line the body-wall, near the anterior end. The 

 testes are formed from cells covering the upper end of the 

 funiculus ; these cells multiply, and become spermatozoa. 



The cells of the funiculus at its lower end give rise 



