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Part III — Sixteenth Annual Report 



it appeared to me that the nature and composition of this fluid might 

 be closely related to that which enters the eggs at maturation, special 

 attention has been paid to it. 



Very little seems to be known concerning the normal ovarian fluids of 

 any group.* The only reference I have found to it in Teleosteans — 

 apart from the mere statement of the presence of a "lubricating" fluid — 

 is in a paper by Hensen on the occurrence and quantity of the eggs of 

 some Baltic fisbes.t Hensen, in order to determine the precise specific 

 gravity of the mature eggs of the cod when they are expelled from the 

 oviduct, first ascertained the specific gravity of the eggs and fluid com- 

 bined, and then the specific gravity of the fluid when separated from the 

 eggs. He found the fluid from the ovaries of the cod to have a specific 

 gravity, as determined by the piknometer, of r01115, at a temperature of 

 8*7° C. ; he described it as alkaline and as containing an albuminoid sub- 

 stance which separated on boiling or by the addition of acetic acid, and 

 which on precipitation by alcohol could not again be dissolved. He 

 found the quantity of the liquid to vary greatly, but to range as a rule 

 between fourteen and twenty per cent, of the total volume of the matter 

 discharged from the ovaries in the cod. Hensen supposes the fluid to 

 originate in the Graffian follicles, and he terms it accordingly liquor 

 folUculi. 



Before I was aware of Hensen's observations I examined the fluid from 

 the ovaries of certain species by cutting open the organ and suspending it 

 over a beaker covered with muslin. In this way from the ovaries of a 

 ling, which had just begun to spawn, and which (the ovaries) weighed 

 51bs. 6|oz., the quantity of fluid which drained off in the course of fifteen 

 hours was 122 cubic centimetres. From the ovaries of a cod, which had 

 been spawning for a short time, and which weighed 61bs. 2oz., the 

 quantity in thirteen hours measured 182 cubic centimetres ; and in the 

 same period the ovaries of a saithe weighing 31bs. 2oz., in which the great 

 mass of the organ was composed of mature transparent eggs, yielded 78 

 cubic centimetres. In each case the fluid was a little turbid and left a 

 very faint stickiness on the fingers ; it had a saltish taste, was practically 

 neutral in reaction, and on heating it a fairly copious white coagulum was 

 formed. The specific gravity, determined by a hydrometer, was after 

 correction for temperature 1*012 in that from the ling, and 1*0119 in 

 that from the cod. This method was, however, unsatisfactory, inasmuch 

 as small blood-vessels were cut in slitting up the tissues, and the fluid 

 sometimes possessed a faint sanguineous tinge ; the microscope also 

 showed the presence of a few yolk spherules from ruptured eggs. I 

 therefore adopted the method employed by Hensen, and in the case of 

 the plaice by draining 517 cubic centimetres of eggs and fluid from ripe 

 fish through silk netting the quantity of fluid separated was 51*5 cubic 

 centimetres ; but a considerable amount of course remained adherent to 

 the eggs. The fresh ovarian fluid of the plaice was handed to Dr. Milroy, 

 who found that it had a specific gravity of I'OllG, as determined by the 

 piknometer, with a neutral reaction, that it was very pale yellow, almost 

 transparent, and contained a large amount of chlorides, phosphates being 

 absent. The amount of chloride of sodium present was 0*766 gramme 

 to each 100 cubic centimetres of the fluid, and the total of the albumins 

 was 0*838 gramme. More recently Dr. Milroy has examined other 

 specimens of the fluid from the ovaries of Teleosteans, which will be found 

 described at p. 135 of this Report. 



* Hammarsten. Lehrbucli der Physiologisclien Chemie. 1895. 



t Vierter Berich. d. Korn. ::. Wiss. Untersach. d. deutscJien Metre. 1884. 



