We do not know of any freshwater sponges from German South-West- 

 Africa. The collecrion described in this paper was made in August, 1911, 

 in the Zambesi, at a point near the Victoria Falls and aetually in Rhodesian 

 territory though only a few miles from the frontier. It is at any rate 

 most probable that the species also occur some miles further up in the 

 Zambesi in the German Zambesi territory. Although small, the collection 

 is of considerable systematic and geographieal interest. Four species are 

 represented, of which three are new to science, while the fourth, although 

 known to be widely distributed in Tropical Africa, has not been found 

 pre\'iously in the Zambesi System. All this is noteworthy in view of the 

 fact that sponges have been collected at the same place on two former 

 occasions'), and that no single species is represented in any two collections 

 — an excellent illustration of the wealth of the Inland sponge-fauna of 

 Tropical Africa. 



I have to thank Dr. W. Michaelsen for sending his collection to 

 Calcutta for me to examine. The Identification of the species has been 

 greatly facihtated by the presence in the Indian Museum of schizotypes of 

 most of the African Spongillidae preserved in the coUections of the British 

 Museum and the Natural History Museums of Berlin, Hamburg and 

 Amsterdam. These we owe to the kind ofiices of Mr. Kiekpatrick, 

 Dr. Weltner, Dr. Kraepelin, Dr. Max Weber and Dr. Michaelsen himself. 



The exact locaHtv^ of the 4 species of the collection is: Rhodesia 

 River Zambesi near the Victoria Falls, on the under-side of stones 

 in shallow water off the right shore some 150 m above the brim of „Cataract 

 Fall" 2); W. Michaelsen, 18th August, 1911. 



') See KiRKPATKiCK, Proc. Zool. Soc. London, 1906 (i), p. 218. 



^) See the landscape of Fig. 14 in the „Reisebericht" of this volume. p. 50. 



