AQUATIC PLANTS IN POND CULTURE. 



11 



of some of this luxuriant growth would have resulted in a decrease 

 in the production of young fish is theoretical. This station had been 

 in operation nearly thirty years, and the lakes contained an unusually 

 large number of plants, upon Avhich JNIr. C. K. Green, the last super- 

 intendent of the station, makes the following observations : 



The hornwort {C eratojjhyllum demersum) is especially good as a 

 food producer and for shelter, and is fairly good for shade; is a good 

 oxj^genator and a good aquarium plant, has little root anchorage, and 

 will srow over hard bottom. It is found in 2 to 4 feet of water, ex- 



FiG. 3. — Iloi-nwort {CcratophyUum demer- 

 sum). Found ill ponds and slow streams 

 throughout North America, except extreme 

 north. (After Britton & Brown.) 



Fig. 4. — Fanwort (Cabomba 

 caroliniana). Found in 



ponds and slow streams, 

 southern Ulinois to North 

 Carolina, south to Florida 

 and Texas. (After Britton & 

 Brown.) 



tending to the surface, but not above it. The superintendent consid- 

 ered it the best plant in his ponds. 



Fanwort {Cabomba caroliniana) also is especially good as a food 

 producer, for shelter, and for aquarium work, and is given second 

 place. It is regarded as a good oxygenator and fairly good for shade 

 and, like the hornwort, has little root anchorage and will grow on 

 hard bottom. It is found in 1 to 4 feet of water, and extends nearly 

 to the surface. 



The curled-leaved j)ondweed {Potamogeton crispus)^ a good food 

 producer and oxygenator, good for shelter and for shade and orna- 

 ment, is one of the earliest plants to put forth shoots, and is there- 

 fore valuable for early-spawning fi.shes like the goldfish and carp. It 



