Still another method, if space and neighbors permit, is to bring in a 

 large mass of vegetation, gathered without disturbing it much, and put it into 

 a container with just enough water to cover it. In a day or so the vegeta' 

 tion will start to decay and the animal population will seek the surface in 

 search of oxygen. Hydra may often be collected by the hundred by this 

 method. 



For larger aquatic animals the dip-net, seine and all the apparatus of 

 the fisherman may be used. Sections of minnow seine make excellent material 

 for constructing dip-nets. This material may be purchased by the yard. A 

 one-man seine from two to three feet long and one and one-half to two feet 

 high has the advantage of being small enough so that the operator can take 

 a pole in each hand and push the net before him through the water. For 

 fresh-water clams, a rake or a modification of the commercial "crowfoot" may 

 be used to advantage. Some form of dredge may be used for bottom fauna, 

 if the collecting is done from a boat. Before resorting to seines or traps, one 

 should consult the game laws carefully, as some states have rigid restrictions. 



The smaller land animals are usually to be found in moist or sheltered 

 locations, such as in woodlands under fallen logs or loose bark. Snails, insects 

 and many other invertebrates are often collected most easily after a rain. 

 Then the snails leave their hiding places and insects are less likely to seek 

 safety in flight. For ecological studies dealing especially with terrestrial insects, 

 the piece of collecting equipment most frequently used is the sweep net, a 

 fine, light-weight net designed for use among bushes, grass and other low 

 vegetation. 



Most of the vertebrate animals are either naturally crepuscular or noctur- 

 nal, or else have had such habits forced upon them by man. Years ago market 

 hunters rcaliAcd this and resorted to jack-lighting or hunting the animals wdth 

 the aid of artificial light, finding that even the large game animals are then 

 much less timid than by day. Fortunately the tendency today is to give 

 an animal a fair chance, and such means of hunting are outlawed, but the 

 student of animal life may well adopt this method for less destructive pur- 

 poses. Many fish, most amphibians, and many reptiles and mammals are 

 active and may be watched after dark, showing little of their daytime timidity. 

 Several naturalists have taken advantage of nocturnal habits to obtain unusual 

 flashlight photographs of our wild animals. 



For a closer study and appreciation of the lives of the small animals, 

 the maintaining of aquaria and terraria is recommended. For an aquarium 

 a glass container or even a water-tight wooden bucket or tub may be used. 

 A metal tank is likely to give off injurious materials to the water, unless 

 thoroughly seasoned. The shape of the container should be such that there is 

 plenty of water surface exposed to the air for the absorption of oxygen. This 

 requirement rules out the fish globes of past popularity. If a choice is pos- 



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