AXGUILLA VULGARIS. 377 



The reproduction of the Eel is still imperfectly understood, and from the 

 time of Aristotle has been a mystery which invited the wildest conjectures. 

 As Eels were seen at times to come out of the mud, they were supposed to be 

 bred in the mud. The viviparous Blenny (Zoarces viviparus), popularly known 

 in Germany and Italy as the Eel-mother, has been supposed to be the parent 

 of Eels. In many parts of England village people still believe that Eels are 

 generated out of hair from a stallion's tail, cut into short lengths. The eggs 

 were discovered nearly simultaneously about 1780 by Mondini of Bologna, and 

 O. F. Miiller ; but it was not till 1838 that Rathke described the ovaries fully. 

 They are two yellowish or pale-red band-like organs, as wide as a finger, which 

 extend along both sides of the vertebral column for nearly the whole length of 

 the visceral cavity. They are broadest in the middle and become narrower 

 behind, where they are closer together. They have numerous transverse folds, 

 which are narrow, but somewhat unequal in size, and the folded appearance is 

 lost posteriorly. There is no oviduct, and the eggs are discharged into the 

 cavity of the body, and make their exit by two apertures, covered by a 

 membranous fold, between the vent and the urinary opening. The ovaries 

 contain so much fat, that, although very conspicuous, their true nature is easily 

 overlooked ; and the eggs, being immature, are commonly only one-tenth of a 

 millimetre in diameter, and therefore only to be discovered by the microscope. 

 Each egg is surrounded by a net-work of fat cells ; but in a young fish of 

 twenty centimetres there is much less fat, and the eggs are more easily found. 

 The number of eggs may be estimated at many millions. The male Eel was 

 discovered by Syrski in 1873. It is smaller than the female, being rarely over 

 fifteen inches long. It is found only in brackish water, and in the sea. The 

 male contains, in place of the ovaries, a milt of different shape. This consists of 

 two tubes which run down both sides of the abdominal cavity, and in the middle 

 of their length have an immense number of small vesicular expansions. It is 

 as difficult to discover ripe spermatozoa in these organs, as to find eggs in the 

 ovaries of the female. The male fish has a more pointed head, with large eyes, 

 lower dorsal fin, darker back with stronger metallic lustre, and a white belly. 



There are some early statements that Eels of the most minute size have been 

 taken in ponds where those ponds are unconnected with streams; which seems 

 to leave the question open whether there may not in some localities be land- 

 locked races of Eels. 



The Eel is stated to spawn once in its life and then to die. Benecke quotes 

 some observations made by Dr. Jacoby at Trieste, in which it is affirmed that 

 the dead bodies of female Eels, with the ovaries empty, are seen in great 

 numbers floating off the mouths of rivers ; but confirmation of so interesting 

 an observation is desirable. 



