OVARIES OF THE EEL. 



643 



descent! between the abdominal partition and the folds and leaflets of tin; ovary in the above-men- 

 tioned furrow, and from it pass to the genital aperture without scattering in the abdominal cavity. 



f'i-i' <>f il, natural siz<~. " : i'h 



OVarit'it I' ':>',! in lrilii,',:'fi */d rows, 



tut its vurfacf. 



Tin- shorter border attached to the dorsal wall 

 of the abdomiual cavity ; the longer being 

 free. 



FIG. 3. 



I.- gottb fin'! <*< i'i'l }'! if'irti. one Innr 



</ ,' :! tin/:., ! . niltt! < :: . . ... tTtllU 



imri'iit I'.;,/* .' . , and 



th> ;/</ it" fiiit" 1 ' .' 



As to the development which the ovaries undergo, I have observed from the end of November 

 till the beginning of March, in many adult Eels, of the length of f30 millimeters and more, that 



the ovaries were of the breadth of fifteen to twenty-five 

 millimeters, and of a yellowish and sometimes reddish- 

 white color, produced by the development of adipose tissues 

 and of the blood-vessels and not by the eggs filled with 

 little globules of fat; the genital aperture and the fissura 

 recto vesicnlia were open. 



In other Eels, of a length sometimes of GOO millimeters 

 and more, I found the ovaries less broad, with but little fat, 

 the natural size, and of a mucous and almost glassy appearance, so that I 

 could discern the so called vesicles and germinative dots 

 (nucJt'i and nucleoli); the genital aperture and the Jiuxnm 



j. ,,<,,//< ..... ti'-r.'i, l 



n. Straight intcstinr. 



l>. Fissnta ivrtu -. < Ir.llLs. 



c. Urinary bladder. 



d. Ann.-. 



e. Partition. 



f. l'roi-iiital opening. 



3 outli't of the genital opening in the nrathra. recto-vesicallti were Closed. 



The ovaries of young Eels, of the length of about 500 millimeters, contained invariably 

 but little fat, and the eggs were without globules. The gradual growth and enlargement of 

 the ovaries go on simultaneously with the opening of the genital orifice. According to the quan- 

 tity of fat contained in the ovaries, they have a mucous and glassy, or more or less opaque or 

 white, appearance, or have small shining dots. From the end of March till October I found in the 

 majority of Eels which I examined, measuring COO to 700 millimeters in length, that the ovaries 

 were scarcely white, and that the genital aperture was closed. The number of eggs contained in 

 both developed ovaries readies, according to my calculation, live millions. The larger e^;^s 

 measured by m<- had a diameter of one-fourth to one-fifth millimeter, while the eggs of an adult 

 'Grongo' (Conger) had, according to my measurements, a diameter of one-third of a millimeter, 

 and those of the '.Mnreua' (.M urn-nit hi-ltma) almost one millimeter, which explains to me why the 

 ovaries of the two last-mentioned species of lish have long since become known. 



In an Eel measuring fi!M) millimeters, examined on the Cth July, the left ovary was entirely 

 wanting, and replaced by a mass of fat. 



THK SPERMATIC OK<; \>s. The position of these organs (Fig. 5), which are not ribbon- 

 shaped like the ovaries, but represent two longitudinal rows, each \\iih about fifty lobules (Fig. G), 

 of the width at most of three millimeters, and found only in Eels not more than 1.10 milli- 

 meters long, corresponds entirely with that of the ovaries. In these organs are likewise found 



