52 MR. E. A. SMITH ON SHELLS [Jan. 17 



4. On the Shells of the Albert Nyanza, Central Africa, 

 obtained by Dr. Emin Pasha. By Edgar A. Smith. 



[Eeeeived December 5, 1887.] 



Among the valuable collections of Natural History recently received 

 from Dr. Emin Pasha are a few shells which he collected in the 

 Albert Nyanza, probably from the eastern side of the Lake. 



They are referable to : — 



1. Melania tuherculata, Miiller. 



2. Melania liricincta, n. sp. 



3. Paludina unicolor, var. 



4. Bythinia alberti, n. sp. 



5. Planorbis stanleyi, n. sp. 



It is not surprising that three out of these five species should be 

 undescribed, as, with one exception, no collections of shells have ever 

 reached this country from this particular region. 



In 1866 Mr. Henry Adams gave a list, in the 'Proceedings' of 

 this Society (p. 37.'5), of a collection of shells made in Central Africa 

 by Sir Samuel Baker, the discoverer of the lake. I am informed 

 by that gentleman that all the shells mentioned by Mr. Adams, 

 and which he has presented to the British Museum, came from the 

 Albert Nyanza. 



Through the kindness of the Rev. Horace Waller I have had the 

 opportunity of examining a series of shells from the same locality, 

 which he also received from Dr. Emin. Among them are examples 

 of two new species, a Cleopatra and a Bythinia, which are not repre- 

 sented in the two other collections. 



Altogether fifteen species are now known from this particular 

 lake, and of these seven appear at present to be peculiar to it. The 

 remaining eight have all been recorded from different parts of the 

 Nile, and one species, Melania tuberculata, is also known from 

 three of the other large Central African lakes, namely Nyassa, 

 Tanganyika, and Victoria Nyanza. The Planorbis sudanicus also 

 occurs in Lake Tanganyika. 



The following is a complete list of the known species from the 

 Albert Nyanza. 



1. Melania tuberculata, Miiller. 



A large series of this remarkably distributed species has been sent 

 by Dr. Emin Pasha. A dark purplish brown or black is the pre- 

 vailing tint of most of the specimens, with only slight indications of 

 the spotting which is characteristic of the species. Some of the 

 examples, however, possess the usual style of colouring, being pale 

 olive or dirty white and dotted and spotted with red. 



2. Melania liricincta, n. sp. 



Testa elongata, turrita, sub epidermide nigra -fusca albida ; anfr actus 

 persistentes 5, parum convext, interdum inferne leviter tmnidi. 



