FAUNA OF THE AFRICAN LAKES. 593 



Text-figuie 1. 



Curve showing groioih of knowledge oj Tanganyika fauna. 



500 



400 



300 



200 



100 



0 





























p 













— 



/ 1 



STAf*, 











X Co 



t — 



1 





so 



1 









1 







1850 I860 1870 1880 1890 1900 I9ld I9?0 



The relative peculiarity of each lake fauna, as far as totals only 

 are concerned, can be best illustrated by giving the figures in 

 pai-allel columns with the marks E or P against them. 





Tan^i-au- 

 yika. 



Victoria 

 Nyanza. 



Nyasa. 



Albert 

 Nyanza. 



Edward ^a- 

 Nyanza. 



Genera 



57 E, 111 P. 



(168) 



2E, 137 P. 



(139) 



6E, 172 P. 



(178) 



1 E, 47 P. 



(48) 



IE, 34 P. 13 P. 



(35) 



Species 



293 E, 109 P. 

 (402) 



110 E, 179 P. 



(289) 



86 E, 275 P. 

 (361) 



9E, 58 P. 



(67) 



HE, 43 P. 4E, 19 P. 

 (54) (23) 



An examination of these totals at once reveals the chief points 

 in which the fauna of Tanganyika is distinct. In the first place, 

 the lake contains a more extensive series of forms (402) than any 

 other. In the second place, those types greatly predominate 

 which are unknown elseAvliere (293 out of 402). Both these 

 points, viz. total number of species and cori'esponding number 

 of endemics, are shown graphically for each lake in the following 

 tabk- : — 



