300 



AMERICAN FORESTRY 



DRAGON FLY 



Young Dragon flies, known as nymphs, live a 

 the structure and history of these form one of 

 chapters in the entire range of entomology. 



subaquatic life, and 

 the most remarkable 



cal situation. Naturally, we would not look for salt- 

 water marshes above sea-level, and we do not meet with 

 ponds in mountainous districts; while as to their geo- 

 graphical locations, it is hardly necessary to point out 

 that in New Jersey, for example, one would find very 

 different species of animals in ponds and marshes of all 

 descriptions, from the ones met with in any of the Pacific 

 tier of States ; those in New England would be different 

 from the ones found in Florida, or in Texas, and so on 

 for other regions. 



Another matter is the fixity of certain forms in their 

 habitats, by which is meant the inability of certain 

 species, through the exercise of their own powers, to 

 quit their normal habitat and pass to another more or 

 less distant. For example, fish in ponds where there are 

 no means of escape either through aqueous connections 

 or through inundations, are confined for life to those 

 pools or ponds wherein they first saw the light ; and 

 this is also true of many of the lower forms of animal 

 life, especially of the larvae of certain insects. However, 

 in the case of the latter they have the power to travel at 

 large when they assume the adult stage. Nymphs of 

 dragon-flies, for instance, when brought forth in an iso- 

 lated pond, remain in it until they pass to the fly-form, 

 whereupon they roam about on wing as far afield as 

 they please. 



Minks, otter, muskrats, and other mammals more or 

 less aquatic by nature, may remain in certain parts of 

 swamps, or make their home in suitable ponds, and stay 

 there for the rest of their lives ; though this only hap- 

 pens when they are not molested or harrassed by man. 

 But if this comes to pass, and they can get away in 

 safety, they will soon migrate to other sections where 

 the needed seclusion may be enjoyed. 



In the more northern parts of the country the feathered 

 residents of ponds and marshes are, as a rule, of the 

 migratory order; so that, when winter sets in, they take 

 themselves off and fly southward. In warmer climates, 

 in the Southern States, the extent of bird-life to be 

 found about marshes and ponds will depend on to what 

 extent they are harassed or destroyed by man, and upon 

 the amount of plant, shrub, and tree-growth to be found 



happen where the marsh is a 

 salt-water one. It can only be 

 affected where extensive changes 

 take place in the area in which 

 such a marsh exists. 



As to the animal life in fresh 

 and salt-water ponds, in fresh 

 and salt marshes, or in combi- 

 nations of any of these, it dif- 

 fers very materially and for 

 evident reasons. In addition to 

 the difference in the nature the 

 chemical nature of the element 

 in which the various animals are 

 called upon to live, there is the 

 matter of altitude and geographi- 



TADPOLES ARE INTERESTING TO STUDY 



Bull-frog tadpoles, of which one is here shown natural size, make very instructive forms to rear 

 in aquaria. This one's hind legs were just appearing; the fin to the tail is quite translucent, while 

 many of the life-phenomena of all animals may be studied in this creature. 



