PRACTICAL CARP CULTURE. 58 



moment of contact. After one female has deposited all her eggs, others 

 are induced to do the same on the same leaf; thus leaves may be found 

 containing, in large patches, deposits in different stages of maturity; 

 some ready to hatch, while others may have been deposited only an hour 

 before. The male remains below the leaf until the eggs are all hatched, 

 allowing nothing to approach them. He does that with so much energy 

 that even carp fifty times his own size he will attack and drive away, and 

 should a dragon-fly alight on his leaf, he will jump out of the water and 

 scare it off'. 



As the minnow is very destructive to fish spawn himself, he seems to 

 judge others by his own character, and with good reason, as such deposits, 

 deprived of his protection, are invariably soon devoured by other fishes. 



The black-headed minnow begins to spawn at the age of one year, be- 

 ginning early in the spring and continuing throughout the summer. Their 

 eggs hatch after four to six days, according to the temperature. The male 

 attains a size of three inches, while the female rarely measures more than 

 two inches in length. When quite young, minnows swim in shoals near 

 the surface. 



Although minnows are not a worthless fish in one sense of the word, 

 as they constitute the almost exclusive food of many of our table fish, 

 tluy are a nuisance to the fish-culturist, and may be ranked among fishes 

 as the English sparrow is among birds. Its destructiveness knows no 

 limits; it devours spawn and young of other fish, and continually wor- 

 ries other more useful and peaceful varieties. The species above described 

 frequent water of any quality, and it is often wondered how minnows ever 

 came into certain water basins which had no connection whatever with 

 creeks or springs. This, however, may be explained by considering the 

 adhesive nature of their eggs, and the fact that frogs and toads frequent 

 the same waters and deposit their spawn upon similar objects and at the 

 same time as the minnow. What would be more natural than to suspect 

 that these amphibians transplant the eggs from one locality to another on 

 the moist skin of their backs? The practical aspect of this discovery the 

 pisciculturist will readily appreciate, for he can exclude the destructive 

 minnows by excluding the frog and toad, when already present, by de- 

 stroying their spawn or capturing the male from under the leaf. 



INSECTS, LARV/E, AND BUGS. 



Carp ponds have suffered far more from this class of enemies than 

 rulturists are generally aware of. A knowledge of their habits and 

 natural history is essential to successful protection against their ravages, 

 which are confined largely to the eating of the fish eggs, and capture of 

 the young fish under two inches in length. Prominent among those that 

 feed on the eggs, but do not harm the fish, is 



THE WATER A SELL. 



(Asellus aquaticusO 



The illustration presents a good idea of this little crustacean, which is 

 not more than one-half of an inch long. It crawls upon.the bottom of the 



