82 I)i". AV. A. Ommington on the 



It is ncccs>;ary to cx[)lain lliat the form referred to as 

 Ct/chps oilhonouhs, &irs, is in all probability not that .sj)eeie.s, 

 wliicli was oiiginally described from Europe, but another 

 which is widely distributed in Africa. On this point I have 

 consulted Prof. Sars, than whom there could be no more 

 comjietent authority, and I must express my indebtedness 

 to him for writing to me about the matter at some length. 

 As important questions of synonymy are involved, perhaps I 

 may be permitted to quote from liis letter. He says : — "The 

 occurrence in Africa of the true C. oithonoides, G. O. Sars, 

 has not yet been ascertained. What is so named by van 

 Douwe and other authors is not that s])ecies, but either 

 C. hiialiniis, liehberg (=. (7. cras^us, Fischer), or G. m'f/Iecius, 

 G. U. Sars, probably the hitter species. Tlie only place in 

 Africa where I have noted the former species is from the 

 neighbourhood of Cape Town, These two species are very 

 similar as to the outward appearance, though easily distin- 

 guishable by the relative length of the innermost caudal seta, 

 which in C. hi/ah'7H(s is about as long as the outer medial 

 one, whereas in C. neglectiis it is scarcely more than half its 

 length. Both these species are quite certainly specifically 

 distinct from C. oithonoides^ wd)ich is of a much more slender 

 form of body." (Compare also Sars, Proc. Zool. Soc. 1909, 

 p. 51.) 



In one of the tow-nettings collected by Dr. Leiper I found 

 very unexjjectedly a young Argulid, so that a representative 

 of this quite distinct group of parasitic Copepoda is to be 

 included among the Entomostraca of the lake. The specimen 

 is probably a male larval form of Argulus africanus^ Thiele. 

 It has already been referred to in my report on the Branchiura 

 of the Third Tanganyika Expedition (Proc. Zool. Soc. 191o, 

 p. 279). 



The only record of Cladocera, so far as I am aware, is that 

 given by Brehm in his account of the Cladocera of the Duke 

 of Mecklenburg's first expedition (Wiss. Ergebnisse d. D. 

 Zentral-Afrika Exp. 1907-1908, Bd. iii. 1912, p. 167). 

 From the tow-nettings taken in Lake Albert he obtained a 

 single species of Daphnid, which he has described (p. 169) 

 under the name of Dapline * monacha, sp. n. It is a form 

 belonging to the magtia group. The Cladocera contained in 

 Dr. Leiper's material I had intended to work out myself, but, 



* I cauuot agree that it is necesEary to reject the name Daphnia, 

 ■vvhich is almost universally applied to this genus, fn a later paper on 

 tlie Cladocera of the Second German Central Africa Expedition, Brohm 

 himselt' refers to the genus as Daphnia. 



