344 MR. E. A. SMITH ON SHELLS [Apr. 20, 



of 5 to spinners; h, length of $ to extremity of abdomen; /, length 

 of ^ to extremity of abdomen ; g, length of (^ to spinners ; 1(3 h, pro- 

 file of eephalotliorax ; 16 c, abdomen of cj' on upperside ; 16 c, abdomen 

 of 5 ill profile. 

 Fig. 17. Argyrodcs ohfiisa, sp. n., S2:iider in profile. 



Ii, profile of ceplialothoi-ax ; c, caput from in front ; j, length of 

 Spider to extremity of abdomen ; /.', length of Spider to spinners. 

 17 «'. Arfii/rodcs ainplifrons, sp. n., Spider in profile. 



d', length of Spider to spinners ; c' , length of Spider to extremity of 

 abdomen ; 17 b' , profile of eephalothorax ; c', caput from in front ; d', 

 profile of spider ( $ ) ; c', extremity of abdomen ( c? ) ; /', extremity of 

 abdomen (cJ)i from below; g, length of J to spinners; /;, length of 

 2 to extremity of abdomen. 



13. Arggrodcs scvfubcrculafa, sp. n., Spider in profile. 



(', profile of eephalothorax ; h, abdomen from above ; c, length of 

 Spider to extremity of abdomen. 



14. Arggrodcfi ididans, sp. n., Spider in profile. 



a, profile of caput ; b, caput from in front; c, length of Spider ((j') 

 to .spinners ; d, length of Spider ( <?) to extremity of abdomen ; c, length 

 of § to extremity of abdomen ; /, length of $ to spinners. 



15. Argyrodcs infcUx, sp. n., Spider in profile. 



«, abdomen on upperside; i, length of Spider to spinners ; c, length 

 of Spider to extremity of abdomen. 



19. Argyrodi:s fcUx, sp. n. 



«, Spider in profile ; b, length of Spider to spinners; c, leugtli of 

 Spider to extremity of abdomen. 



20. Arggrodes nigra, sp. n. 



a, Spider in profile; b, Spider in profile, from upperside; c. length 

 to spinners ; d, length to extremity of abdomen. 



4. On the Shells of Lake Tanganyika and of the Neighbour- 

 hood of Ujijij Central Africa. By Edgar A. Smith. 



[Eeceived April 6, 188(\] 

 (Plate XXXI.) 



In the year 1877 I had the pleasm-e of communicating to the 

 Society a paper on the shells found in Lake N} assa. It is now my 

 privilege to lay before it an account of the known mollusks inhabiting 

 another of the large African lakes, namely Tanganyika. 



Mr. Edward Coode Hore, of the London Missionary Society's 

 Tanganyika Mission, stationed at Ujiji, sent a collection of shells to 

 his brother, Mr. John Coode llore ; and the latter has liberally pre- 

 sented them to the British Museum in his brother's name. 



The only shells hitherto recorded from this particular region were 

 collected by Captain Speke some twenty years ago, and described in 

 these 'Proceedings' (1859) by Mr. S. Woodward; they were four 

 in number, viz. Pleiodon sjjekei, Lithoglyphus zonatus, Melania 

 nassa, and Unio burtoni. The last of these is the ( nly form not 

 included in Mr. Ilore's collection. 



The latter comprises twenty-one species, nine of whicli are new 

 and inteicsting forms. Of these I would particularly call attention to 

 Tiphobia horei and Neothauma tanganyicensis, both of which are new 



1 



