Forest and stream . l and shallow ponds in whichmany water plants are growing are best for malcing col-lections. By taking the trouble to make a net of sometine woven material—mosquito netting will _ do for thelarger forms—a much larger number and variety may beobtained. They may be kept alive in the jar for a long-time if a water plant or two be put in with them andwater is added daily to make up for evaporation. Inthis way an interesting aquarium is made. Let us examine some of these lively little creatures andfind out where they belong in the great world of livingthings and, as far as we ca
Forest and stream . l and shallow ponds in whichmany water plants are growing are best for malcing col-lections. By taking the trouble to make a net of sometine woven material—mosquito netting will _ do for thelarger forms—a much larger number and variety may beobtained. They may be kept alive in the jar for a long-time if a water plant or two be put in with them andwater is added daily to make up for evaporation. Inthis way an interesting aquarium is made. Let us examine some of these lively little creatures andfind out where they belong in the great world of livingthings and, as far as we can, how they live and move andhave their being. Suppose we begin with this little fel-low, just large enough to he readily seen, which swimsalong with a jerky motion and which is easily distinguishedfrom all others of its kind by possessing a single eye di-rectly in the middle of the head. Its name is Cyclopsand it belongs to a group of small crustaceans calledEntomostraca, or, in common language, waterfleas. One. notices its long antennas which seem to serve as swim-ming organs as well as feelers, its short kicking legs, itsringed abdomen or tail which terminates in two longwhips which seem to serve as rudders. If it is a femalecyclops we are examining our interest will at once becentered in the two large sacks attached at the sides ofthe abdomen and filled with what one woidd at once guessto be eggs. Eggs they are, and being carried about bythe parent in this way their chances of development are,no doubt, very much better than they would be if theywere set free in the water and exposed to the danger ofbeing devoured by some hungry creature. When theyhave reached a due state of maturity they escape the sack,and it has been found that their subsequent developmentis through a series of remarkable changes, though notuncommon in the group of animals to which they pass into what is called the nauplius form, an or-ganism very different in appearance to an adult cyclop
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectf, booksubjecthunting
