OVARY AND OVARIAN OVA IN CERTAIN MARINE FISHES. 153 



which here and there perfect eggs were distributed either 

 singly or in small groups. Brock remarks that these specimens 

 show that the abortion of sexual cells takes place in tlie female 

 sex as well as in the male^ but that at the same time the fact 

 that the condition in question was only observed in isolated 

 cases leads to the conclusion that it is not a constant and 

 regular stage in the history of the ovary. 



My own observations, on the other hand, show that the 

 condition of the ovary here in question is a perfectly constant 

 stage, and that it is due to the remarkable and abundant 

 deposit of fat in the connective tissue of the ovary. The 

 meshes of the network described by Brock are, in reality, fat- 

 cells. In sections prepared by the paraffin method the fat has 

 been dissolved out, but in the fresh state the oily nature of 

 the contents of these cells is perfectly obvious. There is no 

 indication at all of the abortion of ova. The process of such 

 abortion and reabsorption, as it occurs in the ovaries of other 

 species, has been shown in this paper to be manifested in par- 

 ticular appearances produced by the presence of the remnants 

 of the disintegrated ova. No trace of such remnants has 

 been seen in the ovary of the conger, and their absence is in 

 accordance with the special history of the ovary in the eel 

 family — namely, a slow but continuous development culminat- 

 ing in a single and final act of spawning. 



In the conger the fatty condition of the ovary is found from 

 the time when the fish is a little over 2 feet long to that when 

 it is full-grown, 4 to 6 feet or more long, and the ovary begins 

 to assume the ripe condition. In nearly all specimens that are 

 caught in the sea, except the small, in which the ovaries are in 

 the stage previously described, the ovaries are in this condi- 

 tion. 



The third stage in the development of the ovary of the 

 conger is that exhibited by the ovaries of specimens which 

 have died in aquaria with these organs much enlarged, and 

 evidently almost ripe. In these ovaries there are no fat-cells, 

 they have all disappeared, and each lamella consists chiefly of 

 two layers of large eggs not differing from one another very 



