396 BULLETIN OF THE UNITED STATES FISH COMMISSION. 



■weighing, counting, and calculating did not give as reliable a result as 

 Mas the case with the largest fish. For these four I got the following 

 number of eggs: 48,000, 80,000, 108,000, and 116,000; and these figures 

 are certaiuly below the actual number of eggs. All the five flounders 

 together contained 033,380 eggs, which would make the average number 

 of eggs per spawner 120,070. 



As according to the observations of the fishermen there are always 

 two to lliree female flounders to one male, it may be supposed that of 

 the 1,400,000 caught in the Eckenforde waters during the years 187!) and 

 1880, at least 900,000 were spawners. Giving to each of these an average 

 of only 120,000 eggs, the number of flounder eggs withdrawn from these 

 waters would be 900,000 times 120,000 = 108,000 millions, or more than 

 100 milliards, whereby doubtless the number of young flounders in the 

 summer of 1880 had been considerably decreased. For it would be a 

 great mistake to suppose that the withdrawal of so large a number of 

 eggs would do no harm, because the surviving flounders would lay a 

 sufficiently large number of eggs. 



Similar opinions relative to the oyster have induced the oyster fishers 

 on the coast of France and England to entirely ruin their oyster beds. 

 When they had learned that a grown oyster produces 1 to 2 mill- 

 ions young oysters, they thought that a few mother oysters would suffice 

 to rapidly populate again an oyster bed where fishing had been going 

 on. They, therefore, scraped the beds so loug that the work ceased 

 to be profitable. Of the young oysters which develop iu the so-called 

 " beard," between the mantle and the gill-plates of the mother oyster, 

 only a comparatively small number reach suitable places on the bottom 

 of the sea, where they can develop to oysters which are fit to be 

 brought into the market. Many of them get into the sand and heavy 

 mud, in which they are smothered, while others, which have found a 

 suitable body to which to adhere, are eaten by star-fish and crabs be- 

 fore their shell is thick enough to ward off these enemies. 



The eggs of the flounders are also exposed to many dangers before 

 they develop into mature fish. When, coming from the ovaries, they 

 reach the water, the spermatozoa of the milters must enter them, iu 

 order that they may develop. The female does not protect her eggs, 

 but leaves them to their fate. It is likewise certain that many of the 

 impregnated eggs are devoured by other animals before the young fish 

 slip out; and even later many of the young fish become the prey of 

 other fish and aquatic birds, at least as long as they float about near 

 the surface and live in shallow waters near the coast. 



Thus, even under the natural conditions of life, only a small portion of 

 the numberless flounder eggs produced each spawning season ever 

 reach sexual maturity. A large production of eggs in any species of 

 animals is, therefore, by no means an indication that large numbers 

 of these animals will be raised. A female intestinal worm (Ascaris Iiun- 

 bricuidcx) produces about 00 million eggs, and a female tape-worm 





