PRACTICAL CARP CULTURE. ,59 



Their natural enemies are the frog and the water-spider. The latter, 

 small as it is, compared with their own size, is, nevertheless a powerful 

 antagonist, attacking them when in the act of depositing their eggs. The 

 attack is made directly upon the eye, the largest dragon-fly thus being 

 easily overpowered by its small but intelligent enemy. 



How strange it is that just those animals with which man has the 

 least sympathy are among his best friends! Such are the toad and the 

 spider!" 



AN INTERESTING ENEMY. 



Among the* strangest and most interesting enemies of the 

 carp, are a class of carnivorous plants, that until recent years were not 

 known to capture any other animal life than that of insects and the 

 smaller crustaceans. Among the earliest to call attention to the fact that 

 a specie of these plants captured young fish, was Hugo Mulertt, so often 

 quoted in this work, and it is but justice to call attention to this fact, 

 while we give the description and illustration of an other taken from the 

 Bulletin of the United States Fish Commission. 



PISCIVOROUS PLANTS. 



By E. Halperine. 



"The so-called carnivorous plants for some years, especially since 

 Charles Darwin made his interesting researches, have attracted the atten- 

 tion of naturalists, not only on account of the curious phenomenon itself, 

 but more particularly because of the philosophical conclusion which may 

 be drawn from it. 



It is known that the ordinary plants draw from the soil by means of 

 their roots the nutritive inorganic elements which they need, and absorb 

 by means of their leaves and stems the carbonic acid of the atmosphere 

 it has thus been said that the plants play the part of intermediate work- 

 ing agents, transforming inorganic matter into organic elements such as 

 alone can serve as food for beings belonging to the animal kingdom. 



Although it was already known that nitrogenous manures or fertil- 

 izers of an organic nature were just as indispensable for the formation of 

 plants, botanists were nevertheless surprised to learn that in carnivorous 

 plants the absorption of organic elements was no longer going on as usual 

 by means of their roots alone, but also by their leaves, which are more or 

 less adapted to these new functions, secreting a genuine gastric juice, and 

 transforming organic matter by a chemical process identical with the 

 digestion of animals. 



In fact all the experience, and the facts observed by Charles Darwin 

 and his son Francis, by Hooker, F. Cohn, Mrs. Treat, of New Jersey, and 

 many other naturalists, prove sufficiently the fact of animal digestion by 

 the leaves in these plants, particularly in Dioncea muscipula, and in dif- 

 ferent kinds of the Rossolis or Drosera. Many other plants, like the 

 Aldrovanda, Drosophyllum, the Pinguicula, and the Utricularia, of 

 which we shall have to speak specially, have also been mentioned as car- 

 nivorous plants. Professor Hooker adds the Nepenthes, and Drs. Melli- 



