144 The Apodes, or Eel-like Fishes 



may be found in the same waters. It was one of the ideas of 

 the Greek to attribute their paternity, as of many other doubt- 

 ful offspring, to the convenient Jupiter. The statement that 

 they are viviparous has arisen from two causes: one the exist- 

 ence of intestinal worms, and the other from the confusion of 

 the eel with an elongated and consequently eel-like but other- 

 wise very different form, the Zoarces mviparns. The Zoarces 

 is indeed, in Germany as well as in the Scandinavian countries, 

 generally known as the Aal-mutter, or eel-mother, and thus in 

 its name perpetuates the fancy. Even where eels are to be 

 found in extreme abundance, and where they are the objects 

 of a special culture, like erroneous opinions prevail. Thus, 

 according to Jacoby, about the lagoon of Comacchio there is 

 an ' ineradicable belief among the fishermen that the eel is born 

 of other fishes; they point to special differences in color and 

 especially in the common mullet, Mugil cephahis, as the causes 

 of variation in color and form among eels. It is a very ancient 

 belief, widely prevalent to the present day, that eels pair with 

 water-snakes. In Sardinia the fishermen cling to the belief that 

 a certain beetle, the so-called water-beetle, Dytiscus raselii, is 

 the progenitor of eels, and they therefore call this "mother of 

 eels." The assignment of such maternity to the water-beetle 

 is doubtless due to the detection of the hair-worm, or Gordius, 

 in the insect by sharp-sighted but unscientific observers, and, 

 inasmuch as the beetle inhabits the same waters as the eel, a 

 very illogical deduction has led to connect the two together. 



"All such beliefs as have been thus recounted are due to 

 the inconspicuous nature of the generative organs in eels found 

 in fresh waters and at most seasons a characteristic which is 

 in strong contrast to the development of corresponding parts 

 in fishes generally. Nevertheless the ovaries of the eel were 

 discovered, as long ago as 1707, by Dr. Sancassini of Comacchio, 

 and described by the celebrated Valisneri (after whom the 

 plant Valisneria was named) in 1710, again by Mondini in 1777, 

 and almost contemporaneously by O. J. Miiller of Denmark. 

 Later the illustrious Rathke (in 1824, 1838, and 1850) and 

 also Hornbaum-Hornschuch published the results of special 

 investigations, and figured the eggs. But it was only in 1873 

 (after several futile endeavors by others) that the male organ 



