Distribution of Freshwater Fish in Algeria. 383 



Tell in this province, the geological variety in its mountains, 

 the abundance of forests producing shade and coolness on its 

 littoral, and, above all, because the whole of the Saharan de- 

 pression with its bahi's is comprised within its limits. 



The province of Algiers has only six species, of Avhich four 

 are special to it — Cristiceps argentatus^ Gasterosteus hrachy- 

 centrus^ Atherina Rissoi, and Cyprinodon iberiis. 



In the province of Oran an equal number is found ; but of 

 these only one, and that the common goldfish, does not occur 

 in the others. 



It now only remains to make a few remarks on the area 

 which these twenty-one Algerian species occupy elsewhere 

 in the world. 



Amongst those with an extensive geographical distribution, 

 besides the common eel, there is the Cristiceps, which inhabits 

 the Mediterranean, the Atlantic, the Cape of Good Hope, and 

 extends as far as Australia ; the Mugil cdpito^ which frequents 

 the coasts of Europe and Western Africa ; the Clupea finta^ 

 which is found in the Mediterranean, on the west coasts of 

 Europe, and in the Nile ; and the two Gobies, common to the 

 Mediterranean and the North Atlantic Ocean. 



The Mugil cephalus is caught on all the coasts of Africa. 



The Blennius vulgaris^ a Mediterranean sea-fish, is sold as 

 a freshwater one on the banks of the Italian lakes and at 

 Aix-les-Bains. 



The Atherina Rissoi appears peculiar to the Mediterranean. 



The other species, which do not exist out of fresh or brackish 

 water, have a less extended distribution ; nevertheless Cypri- 

 nodon calaritanus inhabits both the north of Africa and the 

 south of Europe. The Chromis nilotica extends from Algeria 

 to Mozambique; and the C. Tristrami has been found also 

 in the kingdom of the Ashantees. 



The Cyprinodon iberus^ as its name indicates, is of Spanish 

 origin ; the Barbus callensis has been found in the Tagus ; 

 and the Gasterosteus brachycentrus is an Italian species. 



It is commonly known that China is the home of the Gar op- 

 sins auratus. 



Algeria possesses five species peculiar to itself : — the Salmo 

 macrostigma^ Avhich loves the cool and limpid waters of the 

 Oued Z'hour and its affluents, which flow over beds of granite 

 and gneiss, through shady cool forests (this is the most 

 southern species of all the Salmon family) ; the Tellia apoda^ 

 Avhich has no known habitat save the spring of Bou-Merzook, 

 from which it never strays more than half a mile ; the Leu- 

 ciscus callensis^ which peoples all the lakes and springs, both 



