Freshwater Fish of Algeria. 387 



made in connexion with the freshwater-fish fauna of Algeria 

 is the occurrence of a well-known Mediterranean Blennioid in 

 an artesian well on the high plateaux of the province of Al- 

 giers. M. Fanton, a naturalist of Algiers, has presented us 

 with a specimen of the common Cristiceps argentatus, Risso, 

 which he assures us he caught in one of the " rigoles d'ecoule- 

 ment" of the Fontaine MalakofF, an artesian well excavated 

 in the vast depression which traverses the route between Al- 

 giers and El-Aghouat, known as the Basin of Zahrez. 



The following is a description of the specimen in question, 

 which differs in some respects from the diagnoses of other 

 specimens with which we have compared it : — 



B.6;D.3|?; A.^; V.i. 



Height of body about 5 times in total length ; head 4 times 

 in the same ; snout of moderate extent, subconical, with 

 the lower jaw somewhat prominent ; no palatine teeth. The 

 width of the interorbital space is half the diameter of the eye ; 

 a small but rather broad fringed tentacle above orbit. 



Scales rather large and very cons'picuous. A well-developed 

 separate dorsal fin on the nape of the neck, supported by three 

 rather stout spines, the middle of which is nearly equal in 

 length to the last of the second dorsal, which latter is united 

 with the base of the caudal. 



Colour, after maceration in spirit, olive ; two longitudinal 

 rows of large brown blotches, about eight or nine in number, 

 along the base of the dorsal and above the lateral line ; a 

 series of white spots below the lateral line ; a narrow band 

 from the origin of the first dorsal, through eye, across cheek, 

 behind mouth ; fins immaculate. 



Length 5^ centimetres. 



Hah. Ain MalakofF. Mediterranean^ Gape of Good Hope^ 

 coast of Australia. 



5. Atlierina Rissoi. 

 fAtherina Rissoi, Cuv. & Val. x. p. 435. 



We think we have recognized in a small Atherina from the 

 Metidja a species very imperfectly described by Valenciennes 

 under the above name, and which does not seem to have been 

 recorded since. If it is not identical with that species, it is 

 certainly a new one. 



D. 6-8 1 jy^^; A. j3^; L. lat. 48; L. transv. 11. 



The root of the ventral falls below the origin of the dorsal. 

 Height of body ^ of the total length ; length of head 4| times 



