1891.] BRITISH CENTRAL AFRICA. 309 



29. Breviceps verrucosus, Rapp ; Cat. Batr. Ecaud. p. 1/7. 

 Lake Nyassa {Universities' Mission). 



Mr. Edgar A. Smith offered the following remarks on the 

 Molluscan Fauna of British Central Africa : — ■ 



So far as I can ascertain, very little seems to be known of the 

 Mollusca of tliis region, and it is only that part of the country near 

 Lake Nyassa and the lake itself which have been partially investi- 

 gated. Sir John Kirk was the first to collect in this district, and 

 the specimens he obtained were described by Dr. Dohrn in the ' Pro- 

 ceedings ' of this Society for 186.5, and by Isaac Lea in the Proc. 

 Acad. Nat. Sci. Philad. for 1864. Some years later Mr. F. A. 

 Simons visited Nyassa and brought home a number of new forms 

 from the lake, which I described in the ' Proceedings ' of this Society 

 for 1877. Finally M. Victor Giraud, whilst travelling in the Lake 

 region, also made collections of shells from Nyassa, which were 

 reported upon by M. Bourguignat^ in 1889. These were obtained 

 at the northern end of the lake, whilst those collected by Sir John 

 Kirk and Mr. Simons were from the southern extremity. 



Judging from what we know of the Mollusca of that part of Africa 

 which lies to the east and south of this district, I do not anticipate 

 that many very remarkable forms will be discovered. Doubtless 

 interesting intermediate links connecting some of the large species 

 of Achatina may be met with, and a number of new species of other 

 groups of Helicidae, besides a few forms of freshwater shells, will be 

 found. It is to be hoped, however, that these conjectures may 

 prove incorrect, and that future investigators will be rewarded by the 

 discovery of many, not ouly new and interesting specific, but also 

 generic forms. 



In Capello and Ivens's work 'De Angola a Contra-Costa,' a number 

 of species collected by those travellers has been enumerated by A. 

 Furtado. Although obtained to the south of British Territory, 

 some of them have already been recorded from the Nyassa region ; 

 and it is therefore probable that others, eventually, will also be 

 found to range as far northward. 



In the following list none of the so-called species characterized by 

 M. Bourguignat are quoted, because, in my opinion, most of them, 

 if not all, are merely varieties of those previously described. 



List of the known Species of Mollusca from Lake Nyassa. 



1. Limncea natalensis, Krauss. 



2. Physa nyassana, Smith. 



3. succinoides, Smith. 



4. Physopsis africana, Krauss. 



Bull. Soc. Mai. France, 1889, pp. 1-40. 



