XXI.-SICKNESS OF THE GOLDFISH IN THE ROYAL PARK, 



BERLIN.* 



Berlin, July 18, 1879. — A destructive epidemic has broken out among 

 the inhabitants of the large goldfish-pond in the "Thiergarten," which 

 rendered it necessary to remove all the fish from the pond last Friday- 

 forenoon. About two weeks ago the park-guards noticed an unusually 

 large mortality among the goldfish. On closer examination it was found 

 that the death of these little fish took i^lace accompanied by very pecu- 

 liar and regularly recurring phenomena. A gathering formed on the 

 head where it is joined to the body, which soon commenced to fester; 

 the head became soft ; the body began to swell considerably ; the scales, 

 which in their natural state lie close and smooth on the body, seemed 

 raised up by a festering substance; the lower gills, which are generally 

 white, had a dark-red color, and a blood-like secretion oozed out of the 

 pores. The poor fish evidently suffered from difficulty in breathing, and 

 kept near the surface of the water. This abnormal condition became 

 more intensified, the fish finally lost their scales and died after three 

 days, often after a few hours. 



The number of dead fish increased from day to day till at last the 

 number of deaths amounted to sixty per day. An immediate examina- 

 tion of this entirely unheard-of i)henomenon was therefore made. Some 

 of the dead fish were taken to the Physiological Institute, where a 

 microscopical examination revealed the fact that these fish contained 

 a large number of living infusoria, which had almost entirely eaten uj) 

 the liver. In other fish, especially those which were particularly 

 bloated, the whole inside was a spongy substance, and various phenom- 

 ena strongly resembled those generally observed in dropsy of human 

 beings. The species of infusoria found inside these fish could not be 

 determined, for it is the first time that infusoria of this kind have been 

 observed at the Physiological Institute. After the character of the 

 sickness had been ascertained, its cause had to be found. It was ascer- 

 tained that most cases of sickness occurred in the northern portion of 

 the pond, where fresh water is introduced. This portion of the pond 

 was carefuUy examined and found to be full of a slimy substance which, 

 . when dried, broke into innumerable fine dust-atoms. 



The supply of water was of course stopped at once, in consequence 

 of which measure the water in the pond has sunk one-half meter. Sci- 



* ^^ Kranlcheit der Goldfische im Berliner Thiergarten." [From "Deutsclie Fisclierei- 

 Zeitung, " second year, No. 29, Stettin, July 22, 1879. ] Translated by Herman Jacobson. 



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