blood, namely, the sedimentation rate. The author concluded that as the maturing of the gonads 

 proceeded, the sedimentation rate increased. 



Working conditions in the open sea have unfortunately prevented us from carrying on simi- 

 lar experiments with the Murmansk herring. 



Drabkina investigated the change in the composition of the blood in pikeperch and bream in 

 the IV and V stages of maturity. She found that the quantity of hemoglobin and the leucocyte form- 

 ula in the bream differed considerably during the ovulation (stage V) from the corresponding fig- 

 ures during the pre -spawning period (stage IV) of the fish. 



Plehn (101), directing the work on fish diseases, states that in healthy fish there are about 

 1, 200 red blood corpuscles for each white one. During spawning, fattening, and various infectional 

 diseases, there is a considerable displacement in this ratio, in the favor of the \NWte blood corpus- 

 cles. 



The relation between the various kinds of leucocytes and the amount of hemoglobin in the 

 blood is thus strongly dependent on the physiological condition of the fish, especially on the stage 

 of maturity of the sexual products . In our study of the sexual cycle of the Murmansk herring we 

 have therefore also concerned ourselves with the composition of the blood. 



Very little is known, not only of the blood, but also of the physiology of the Murmansk her- 

 ring as a whole. The remark by Glebov (13) is very characteristic in this connection. He says that 

 even if a great amoimt of material has been collected for the study of how the outer factors Influence 

 the behavior of the herring, almost no information is available on its physiology . 



For the study of the composition of the blood we used 273 smears and 157 determinations of 

 hemoglobin . 



The blood was taken from the fishes at approximately the same time, between 8 and 11 

 a.m., because the nets were hauled at that time . The herring died very quickly after capture . 

 Only individuals which were alive, and not injured, could be used. 



The coagulation of the flowing blood took place in 5-10 seconds. The blood was taken from 

 the gill artery . The smears were preserved with methyl alcohol for 3 minutes and stained after 

 the method of Glemsa in 50 minutes . The dye was prepared with two drops of Glemsa dye per 1 

 cc. of buffer solution. 



We were interested in the correlation between the composition of the blood and the physio- 

 logical state of the Murmansk herring, particularly the degree of maturity of the gonads . At first, 

 the morphological properties of the blood cells had to be studied. In the literature, no information 

 is available on the blood of the herring, and we had to use the blood morphology classification used 

 for fresh-water fishes. 



From the study of 200 preparations of blood from herrings of varying idiysiological con- 

 dition, we obtained a certain idea of the morphological structure of the blood cells . The non-gran- 

 ular leucocytes are represented by lymphocytes, monocytes and polymorpho -nuclear leucocytes. 

 Of the granular leucocytes, only the eosinophile ones were foimd, containing eosinophile granules 

 of an irregular, rounded shape, and of a dark-brown color. The nucleus is oval, 3.0-5.5 mu In 

 diameter, usually situated at the perlj^ery. 



The structure of the non-granular leucocytes In the blood of the Murmansk herring is slml- 



242 



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