3'° FIRST LESSONS IN ZOOLOGY 



life. Ants, like honey-bees, may be kept in the school- 

 room in a " formicary, ' ' and thus observed at home as well 

 as when foraging in the fields. A "formicary" is simply 

 an artificial nest in which an ant colony has been estab- 

 lished. Professor Comstock gives the following directions 

 for arranging a formicary: 



" The principal materials needed for the construction 

 of a nest of this kind are two panes of window-glass ten 

 inches square, a sheet of tin eleven inches square, and a 

 piece of plank one and a fourth inches thick, twenty 

 inches long, and at least sixteen inches wide. 



"To make the nest, proceed as follows: Cut a trian- 

 gular piece about one inch long on its two short sides 

 from one corner of one of the panes of glass. From the 

 sheet of tin make a tray three-eighths of an inch in depth. 

 This tray will be a little wider than the panes of glass 

 and will contain them easily. On the upper side of the 

 plank a short distance from the edge cut a deep furrow. 

 This plank is to form the base of the nest, and the furrow 

 is to serve as a moat, which is to be kept filled with 

 water in order to prevent the escape of the ants. It is 

 necessary to paint the base with several coats of paint to 

 protect it from water and thus prevent its warping. 



" To prepare the nest for use, place the tin tray on the 

 base, put in the tray the square pane ot glass, lay on the 

 edges of the glass four strips of wood about one-half inch 

 wide and a little thicker than the height of the ants which 

 are to be kept in the nest, cover the glass with a layer of 

 fine earth of the same thickness as the strips of wood, 

 place upon this layer of earth and the strips of wood the 

 pane of glass from which one corner has been cut, and 

 cover the whole with a cover of the same size and shape 

 as the upper pane of glass. In the nest figured the cover 

 is made of blackened tin, and one-half of it is covered 

 by a board. This gives a variation in temperature in 



