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Table 2 Optomotor Reaction (0. r.) of the Autumn Smelt Under the Actionof a Uniform Pulsed Electric Field (f = 30 Hz, T '" 1. 6 msec, V screen '" 60 em/see) Vf, em/see FIeld Strength, Characteristics of the Reaction of the Fish Average under Average after v/cm the action of the action of the current the current Without current 100% o. r. 38 0.073 100% o. r. twitching on switching on the 38 current and on passing electrodes 41 0.11 100% o. r. strong twitching, attempts to 35 32 turn to the anode 0.15 o. r. disturbed in some fish, but restored. 31 strong twitching, turning towards anode 26 0.18 Disruption of o. r., partial restoration. 25 strong agitation, turning towards anode - 0.22 Disruption of o. r., attempts at restora- tion. Turning to anode. Signs of elec- 29 tronarcosis. - 0.26 Disruption of o. r. Electronarcosis - - Note: A total of 63 fish were used in six experiments. v = 75 em/see the reaction was un- screen even the fish made bursts, attempted to swi~ with the screen, but succeeded in doing so only for a short time, IJagged and stopped (Table 1). The optomotor reaction of the smelt was so persistent that its manifestation was not hindered by the presence of extraneous ob- jects In the canal; the fish brushed against the wire electrodes, but contilIl1ed to fal- low the screen. The Influence of a pulsed current on the optomotor reaction of the smelt was studied at V = 60 cm/sec. screen The spring smelt in the channel of the layout began to detect the electric current at a field strength E = O. 07 v/cm, but its optomotor reaction was not disturbed. Re- action to the electric current was expressed only in the twitching of the fish when the current was switched on or when passing tbroagh the anode zone. When field strength was increased (E = - ,;; 0.13 - 0.17 v/cm) the fish passing the anode attempted to turn aside, but this did not prevent them from following the screen. At E '" 0.17 - 0.20 v /cm the fish were greatly stimulated and turned toward the anode; the optomotor reaction was disturbed in some fish. However, apparentiy as a re- sult of adaptation of the organism to the effect of the current, the optomotor reaction was reestablished within 30-50 sec. On move- ment of the fish toward the cathode (rising current) its body twitched. After passing the cathode and entering the field of the falling current (head toward the anode) the swimming of the fish was peaceful. The optomotor reaction of the spring smelt was disturbed both in groups and in solitary fish at E '" 0.20 - 0.23 v/cm or more, when signs of electronarcosis appeared in the fish. However, even at these parameters there were instances of restoration of the optomotor reaction. After cessation of the electric cur- rent disturbing tbe optomotor reaction, the optomotor reaction reappeared in the fish within 10, 20 or 50 see even after a series of stimuli (3-4 times for 1-2 min and 2-3 min intervals). A reduction was noted in the swimming speed of the fish: wbereas before the action of the electric current Vf of the spring smelt had averaged 36 cm/sec (at V '" 60 cm/sec, it declined to 20 cm/sec screen after 3-4 stimuli). The optomotor reaction of the smelt In the autumn under the action of the electric current 606 and without its action was similar to that of the spring smelt. Evaluated results of the spring observations are set out in Table 2. CONCLUSIONS A stable optomotor reaction, the mani- festation of which was not disturbed by the effect of the electric field of a unipolar silIl1soidal pulsed current (f '" 30 Hz, T '" 1. 6 msec), which caused stimulation and produced the threshold of anode elec- trotaxis in the fish, was discovered in the smelt. Considerable adaptation of the fish to the action of the electric current was noted: the optomotor reaction of the smelt was disturbed by a comparatively strong I' electric current, but began to be restored within 30-50 sec. Disturhance to the opto- motor reaction of the smelt was ohserved un- d~r .the influence of an electric field producing dlshnct anode electrotaxis and electronarco- sis. LITERATURE CITED Submitted March 30, 1973 Protasov~ V. R. and Yu. P. Altukhov. 1961. The possibility of using the optomotor re- achon to control the movement of fishes. Rybn. kh-vo, No.2. Pavlov, D. S. 1970. Opto~otornaya reaktsiya i osobennosti orientatsii ryb v potoke vody. (The optomotor reachon and characteristics of the orientation of fishes in a current of water). Moscow, Nauka Press. Blood Protein Composition in the Arol Bream (Abromis bromo orientolis) A. v. Muromtseva Astrakhan Fish Industry and Fisheries Technical Institute , The Aral Sea basin is inhabited by 3 forms of the bream: the "freshwater" form inhabits the fresh waters of the cen- tral part of the Syrdar'ya delta and the in- ner waters of the Amudar'ya; the semi- diadromous form feeds in the sea and moves to the lower reaches of the rivers in the spawning period; the reed bed form is in- variably found in the reed beds in the bays, and also inhabits the Kamyshly-Bash lake system. In addition to these 3 forms we also find the sea bream, which lives and reproduces in sea water with a salinity of 10-11 %.), Some aspects of the ecology of the reed- bed form of the bream are examined in a III1mber of works (FiIatov and Duplakov, 1927; Rylov and Gladkov, 1934; Gladkov, 1936; Morozova, 1944, 1952; Kunin and Doroshev, 1968). The protein composition of the blood serum of the sea, semidiadromous and reed-hed bream is compared in the present paper. MATERIAL AND METHODS We investigated the protein composition of the blood serum in 87 specimens of the sea, semidiaclromous and reed-bed bream caught In a single season and in the same physiological state - maturity stage IV of the gonads. The bream were caught with drag seines in May - early June 1971: the sea bream in Malyy Sary-Chaganak bay (salinity 10%.), the 607