THE TANGANYIKA PROBLEM. 



have not yet been completed, and I propose to treat the 

 whole subject fully here. It is also intended that the 

 descriptions of the anatomy and the conclusions respecting 

 the affinities of the halolimnic gastropods given in this 



sin. 



Fig. 3. — Semi diagram of the anatomy of Typhobia Horei. The Mantle is cut 

 open and the animal viewed from above. The nerves are represented in 

 black, cry st. s., style sac, si., stomach, s/11., gill. 



work shall be understood to supersede any others which I 

 have already published. In what follows there will be 

 found, in the first place, a description of the structure 

 exhibited by each of the different halolimnic molluscs, 

 and, in the second, a discussion of their affinities, based 



