BIHANG TILL K. SV. VET.-AKAD. HANDL. BAND 26. AFD IV. N:0 8. 23 



The following two species of Ahranm are treated of to- 

 gether to allow a closer eomparison of their relative measure- 

 raent such as thev are recorded in the table below: 



Abramis balierus Lin. — A. 



Total length 203 



% of total length: 



Length of head 20,2 



Diameter of eye 5,5 



Praeorbital length 4,9 



Postorbital » 10,3 



Height of body 30,1 



Least height or caudal peduncle .... 8,1 



Distance from snout to dorsal fin ... . 46,8 



* j v ) anal .... 51,3 



» t v. t ventral fins . . . 34,9 



Base of anal fin 34,7 



Height of ■.> 15,0 



Base of dorsal fin 9,1 



Height of » ^ 21,1 



Length of ventral fins 13,3 



' pectoral - 16,2 



Prseabdominal length 16,2 



Postabdominal » 16,2 



If we first compare the Caspian and the Scandinavian 

 Ähraniis haUerns we shall find the following dijöFerences. The 

 former seems to have a somewhat higher dorsal fin, smaller 

 pectoral fins and perhaps also a larger head. The most re- 

 markable diflFerence is, however, that the ventral fins have 

 such a forward position in the Caspian form that the distance 

 between their insertion and the snont is only 34,9 — 36,4 % of 

 the total length, but in the Scandinavian (according to Smitt) 

 the same percentage is 56 — 57. This is still more interesting 

 because there is, as noted above, quite an analogous difference 

 between the Caspian and Scandinavian breams. 



A eomparison between the two Caspian Abramis hallerus 

 and A. sa^ja will give the following result. The head of the 

 former is a little larger, but the eye smaller than in the 



* with pearly excrescences on the head. 



