94 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



XII. Question as to the viviparous nature of eels, — Benecke. 



The discovery of the two sexes has not, however, writes Benecke, set- 

 tled the question whether the eel lays eggs or brings its young alive into 

 the world. There has always been a strong disposition to adopt the latter 

 hypothesis, and there are many people at the present day who claim to 

 have been present at the birth of young eels, or to have found a quantity 

 of young eels in adult eels which have been cut open. Frequently ichthy- 

 ologists hear accounts of occurrences of this kind, and receive specimens 

 of supposed little eels from one to two inches in length, which have beeu 

 kept alive for several days in a glass of water. These are usually thread 

 worms, Ascaris libeata, which live by the hundi^ed iu the intestinal cavity 

 of the eel, and which may be easily distinguished from the eels of the same 

 size by the sharp ends of the body, the absence of lins, of eyes and mouth, 

 and by the sluggishness of their motions. The smallest eels, less than 

 an inch in length, have already the complete form of the adult, and are 

 also transpareut, so that with a magnifying glass one may perceive the 

 pulsations of the heart, and see behind it the brownish-red liver; the 

 mouth, the pectoral, dorsal, anal, and caudal fins are easily seen, and 

 the black eyes cannot be overlooked. In addition to the intestinal 

 worms, the young of a fish of another family, Zoarces viinparus, have 

 given opportunity to the ignorant for many discoveries ; for instance, 

 Dr. Eberhard, in No. 4 of the " Gartenlaube" for 1874, described and illus- 

 trated an '' embryo of the eel," which, in company with about a thou- 

 sand similar embryos, had been cut out of the belly of an eel. This 

 tolerably good drawing at first sight is seen to represent the embryo of 

 zoarces which is almost ready for birth, since it still possesses a very 

 minute umbilical sac. It is very evident that the minute egg of the eel 

 could hardly produce a great embryo with an umbilical sac which exceeds 

 by more than a hundred times in size the whole egg. It is also evident 

 that the imagination of the writer had exaggerated the 200 or 300 young 

 in the Zoarces to a thousand. 



XIII. Hunt foe young eels.— Jacoby. 



As might have been foreseen, remarks Jacoby, Syrski's discovery 

 drew attention anew to the solution of the eel problem. In the spring 

 and summer of 1877, the German and Austrian papers and journals were 

 full of articles and paragraphs upon this subject. Among others the 

 following announcement made the rounds of the press : " Hitherto, in spite 

 of all efforts, science has not succeeded iu discovering the secret of the 

 reproduction of the eel. The German Fischerei- Verein in Berlin offers a 

 premium of oO marks to the person who shall first find a gravid eel 

 wliich shall be sufficiently developed to enable Professor Virchow in 

 Berlin to dissipate the doubts concerning the propagation of the eel. 

 Herr Dallmer, of Schleswig, inspector of fisheries in that province, offered 

 to transmit communications to Berlin, and in 1878, in the January num- 

 ber of the German Fishery Gazette, he published a detailed and very in- 



