of the Fishery Board for Scotland. 



195 



' during the summer, the ovules, in place of having a spherical germinative 

 1 vesicle more or less finely granulated, show the vesicle segmented into 4, 

 ' 8, or a very great number of semi-soJid grayish globules, ovoid in shape, 

 ' when they are from 2 to 8 in number, and spherical and naturally much 

 1 smaller when more numerous.' In an eel 70*7 cm. long, kindly sent 

 from Kilconquhar Loch by Mr Jamieson, Elie, on February 11th, 

 1895, the ova were found to measure 1 8— 22 mm. while some measured 

 •27 mm. The ovum in the fresh condition showed a large mass of oil 

 globules occupying almost the whole of the space within the zona. This 

 collection of oil globules did not take up the place of the nucleus, but 

 simply hid it. When a portion of the ovary was sectioned, the nucleus 

 was seen in the centre of the ovum, surrounded by a large number of 

 empty spaces, which had been occupied by the oil globules. The nucleus 

 contained one large, and several small nucleoli. The mass of oil globules 

 therefore appeared to be a hollow sphere. 



' * The free edge of the ovary of the eel is straight. The organ is all 

 ' of a piece like a ribbon, and not formed like the testicle of a succession of 

 ■ thin lobes, held or bound together at their base alone by the deferent 

 4 canal and the sub-peritoneal cellular tissue. The ovary is supplied by 

 1 vessels from the artery which, with the accompanying vein, runs along 

 ' the adherent edge of the ovary. The arterioles proceed parallel to each 

 1 other at right angles to the adherent edge, until near the free border of 

 1 the ovary. There they auastomose in an arch. The blood is returned by 

 ' veins similarly arranged. The external surface of the ovary is surmounted 

 ' by straight transverse lamelhe, drawn close together, and directed 

 1 parallel to the preceding vessels. They are shorter as the ovary is 

 ' narrow. They terminate at some tenths of a millimetre from the free 

 1 edge of the ovary without reaching it quite. The anastomosing loops 

 ' surround the external or inferior extremities of the projecting lamellae. 

 ' The latter develop more or less in height on the surface of the ovary at 

 ' the time of the maturation of the eggs, and limit, between their surfaces 

 ' of contact, straight furrows. At the bottom of these grooves, in the 

 ' laminae or body even of the ovary are found the vessels indicated above, 

 ' corresponding in some measure to so many intra-ovarian partitions. The 

 1 ovules fill up all the interval between the vessels, and it is because the 

 ' ovules are of greater depth than the ground-tissue, which runs over the 

 ' vessels, that they form the projections on the external surface of the ovary. 

 ' At the time of ovulation these laminae increase in size, and rise much. 

 ' When they hang down they pass beyond the free border of the ovary in 

 ' denticulations. The internal surface, on the contrary, is white and 

 1 shining without little projecting bands, or folds correctly speaking. One 

 ' must not confound these particulars with those which give to the ovary 

 ' the appearance of being plaited like a ruffle. The last tendency results 

 1 from this, that the free edge of the ovary is longer than its adherent edge. 

 * The vessels also, which run from the latter to the free edge, deviate a 

 1 little in approaching the latter. There results then from this the for- 

 ' mation of embossments and cup-shaped depressions, or waving coliar- 

 1 like folds over the whole of the ovarian laminae. These particulars are 

 ' seen especially well in ovaries floating in water in a dissecting tray.' 



Ail the eggs of the eel which have so far been examined have been 

 very small. In the ripe eel described by Rathke, the largest eggs even 

 measured only '1 mm. in diameter. This eel is one of two ripe eels which 

 have been recorded, and it is remarkable that the eggs in this case were 

 much smaller than those subsequently found in unripe ovaries. The 

 largest eggs described by observers have been '27 mm. in diameter. 



* Robin, 1 Les Anguilles males comparees aux femelles,' Journal de V Anatomic 

 et de la Physiologie, 1881, p. 437. 



