THE TANGANYIKA PROBLEM. 



*3i 



Fish es — contin tied. 



Characinid,*;. 

 17. Alestes rueppellii Gthr. 



Cyprinodontid.b. 

 18 Fundulus tceniopygus Hilg. 



1. Limnsea nyanzse Marts. 



2. ,, debaizei Bgt. 



3. Isidora trigona Marts. 



4. ,, strigosa Marts. 



5. ,, transversal is Marts. 



6. ,, forskali Ehrbg. 



7. Physopsis ovoidea Bgt. 



8. Planorbis sudanicus Marts. 



9. ,, choanomphalus Marts. 



10. ,, victorice E. Sm. 



11. Ancylus stuhlmanni Marts. 



12. Ampullaria nyanzse E. Sm. 



13. ,, gordoni E. Sm. 



14. ,, bukobse Marts. 



15. ,, ovata Ol. 



16. ,, emini Marts. 



17. Lanistes schweinfurthi Ancey. 



MORMYRID/E. 



19. Mormyrus oxyrhynchus Geoff r 



20. ,, longibarbis Hilg. 



Lepidosirenid.-e. 



21. Protopterus annectens Ow. 



,, athiopicus Hack. 



MOLLUSCA 

 19 



18. Vivipara unicolor Ol. 



Vivipara rubicunda Marts. 



20. ,, meta Marts. 



21. ,, phthinotropis Marts. 



22. ,, constricta Marts. 



23. Cleopatra guillemei Bgt. 



24. Bithynia humeroso Marts. 



25. Melania tuberculata Mull. 



26. /Etheria elliptica Lm. 



27. Unio lourdeli Bgt. 



28. ,, hauttecceuri Bgt. 



29. ,, multicolor Marts. 



30. Spatha trapezia Marts. 



31. Mutela subdiaphana ligt. 



32. ,, bourguignati Ancey. 



33. Sphcerium nyanza; E. Sm. 



34. ,, stuhlmanni Marts. 



35. Kupera parasitica Parr. 



POLYZOA. 

 1. Species indt. 



The Victoria Nyanza stands at an altitude of nearly 

 4,000 feet. It is higher than either Tanganyika or Nyassa, 

 in most parts its waters are shallow and its shores reedy 

 swamp fringes, but there are many island archipelagoes 

 where the coasts are steep, and the waters which surround 

 them deep and rough. In nature the depression in which 

 the Victoria Nyanza lies is totally unlike those of most 

 of the other African lakes which we have hitherto con- 

 sidered. It is, however, very comparable to the depression 

 occupied by Lake Bangweolo, the Victoria Nyanza being, 

 in fact, nothing more than a gigantic rain puddle, occupying 



