L.M.B.C. TURBELLARIA. 79 



Fig. 16. Copulatory organ of P. fiahellifer, (after v. Graff). 

 Fig. 17. Byrsophlehs intermedia, v. Graff. Natural 



length 1 mm. (X 20). 

 Fig. 18. Copulatory organ of I^. intermedia. 



Plate XIII. 



Fig. 19. AcrorJiynchits caledonicus, Claparede. Drawn 



from the living animal. Natural length 1'5 — 



2 mm. (X 20). 

 Fig, 20. Copulatory organ of ^. caMomcits. 

 Fig. 21. Granule-vesicle of Macrorhynchus naegelii, Koll. 

 Fig. 22. Male genital organs of Macrorhynchus helgolan- 



dicus, Metschnikoff, (after v, Graff). 

 Fig. 23. Hyporhynchus armatus, Jensen. Natural length 



1-5 mm. (X 25). 

 Fig. 24. Copulatory organ of H. armatus. 

 Fig. 25. Vorticeros auriculatum, O.F.M. Tentacles not 



quite fully extended. Drawn from life ( X 25). 

 Fig. 26. Plagiostoma vittatum, Frey and Leuckart ( X 25) . 

 Fig. 27. Provortex halticics, Schultze. From the living 



animal (X 60). 

 Fig. 28. Chitinous copulatory organ of P. halticus. 

 Fig. 29. Plagiostoma sulphureimi, v. Graff. From the 



living animal. Natural length 2 mm. (X 25). 

 Fig. 30. Kipe spermatozoon of P. sidphureum. 

 Fig. 31. Allostoma pallidum, van Beneden. Natural 



length 1-5— 2-5 mm. (X 25). 

 Fig. 32. The genital organs of A. pallidum, (after v. 



Graff). 



Plate XIV. 

 Fig. 33. Pseudorhynchus bifidus,M'lntosh. Drawn from 

 life, showing the anterior conical proboscis. 

 Natural length 1*5 mm. (X 25). 



