the caudal fin. Among the remaining specimens, three represent 17 — 18 

 percent and three 29 — 33 percent respectively. The length of the head 

 represents 33 — 41 percent in 31 specimens and 43 percent in a single 

 specimen only. According to Danilchenko (1947), this species is charac- 

 terized by a small eye whose diameter is equal to the preorbital area. 

 In the material here described, this distance is slightly smaller than 

 the orbital diameter although on some specimens these two figures 

 are in agreement. 



The vertebral column consists of 31 — 32 vertebrae of which 15 — 17 

 occur in the caudal area. On specimens of this species from the 

 Caucasus, Danilchenko (1947) notes always 32 vertebrae. 



The pectoral fins have the longest rays hardly reachinig to the base 

 of the rays of the dorsal fins. 



The ventral fins occur in a position very characteristic of this 

 species. They lie at mid-base of the dorsal fin or just beyond its center 

 (under the 19th — 20th vertebra, from the end); the pre ventral area 

 represents in 24 specimens 54 — 59 percent of the body length without 

 the caudal fin, in 4 specimens 50 — 53 percent, in 2 specimens 60 — 62 

 percent. 



The dorsal fin consists of 11 — 12 rays. It begins before the mid 

 -body, above the 21st — 24th vertebra (from the end). The pi-edorsal 

 area represents 43 — 49 percent of the body length without the caudal 

 fin, but in 21 specimens only 45 — 47 percent, similar to the form from 

 the Caucasus. The length of the dorsal fin corresponds to 6 — 7 precaudal 

 vertebrae, and always exceeds that of the base of the anal fin. 



The anal fin consists of 12 — 13 rays. Its orientation in relation to 

 the dorsal fin is the most characteristic feature of this species. In 28 

 specimens, the preanal area represents 70 — 76 percent of the body 

 length without the caudal fin, as against 72 — 75 percent in the Caucasian 

 form, and 68 and 77 percent respectively in two specimens. In the 

 remaining two specimens, it was impossible to measure the preanal area 

 owing to the bad state of preservation of the anal fin. The beginning of 

 the latter usually occurs at a distance of 3 — 4 vertebrae from the last ray 

 of the dorsal fin, below the 12th — 13th vertebra (from the end), while 

 in the Caucasian forms this distance corresponds to 4 — 5 vertebrae 

 (Danilchenko 1947). 



The caudal fin is shorter than that in forms from the Caucasus, 

 which have the longest caudal rays equal to the length of the head. 



General remarks. The most significant characteristic in this species 

 is the position of the ventral fins, while the distance from the last ray 

 of the dorsal fin to the first ray of the anal fin, and the number of 

 vertebrae, varies but little. In this respect, the specimens described 



30 



