204 ECONOMIC ZOOLOGY AND ENTOMOLOGY 



done in the field, but some species readily live in artificial nests 

 prepared for them indoors. These nests can be so arranged 

 that much of the home life of the ants can be observed. 



A simple formicarium, or ant nest, may be made by mounting 

 an inverted bell glass on a wooden block which is set like an 

 island in a shallow pan of water. Enough of the contents 

 (soil and ants) of a nest should be brought in and transferred 

 to the bell glass to fill it about half full. A cover of dark paper 

 or cloth should be placed around the bell glass as high as the soil 

 fills it, in such a manner that it may be readily removed at 

 times of observation. The ants in their nest building will 

 make some of their run ways and chambers next to the dark- 

 ened glass, and, by removing the cloth, may be seen at work. 



Janet, a distinguished French student of ant life, uses a 

 block of porous earthenware in which several little chambers 

 or hollows have been made, connecting with each other by 

 little surface grooves, the whole covered with a glass plate, 

 and over that an opaque cover. Into a cavity at one end of 

 the block he puts water which soaks some distance along the 

 length of the block, thus rendering some chambers humid, 

 while others at the far end are dry. He gives the ants no soil, 

 forcing them to use the already made chambers. This formi- 

 carium reveals, therefore, none of the secrets of nest-building, 

 but it does reveal admirably a host of those interesting pro- 

 cesses connected particularly with the life history of the individ- 

 uals of the colony. 



Miss Adele Field, an American student of ants, has devised 

 a nest (Fig. 93) in which glass is used for the base, outer wall 

 and partitions. A bit of sponge, kept moist, is placed in one of 

 the rooms. The glass base is double thick and placed on thick 

 white blotting paper for background, and the walls and parti- 

 tions are narrow strips of glass glued to the base with crockery 

 cement. On walls and partitions are glued strips of Turkish 

 toweling. On this is laid a thin glass roof frame for each room. 

 An outer removable roofing of blotting paper makes all the 

 interior of the nest dark, except the food room which should 

 not be covered as it represents the ants' outer world. 



Sponge cake, apple, mashed walnut and the muscular parts 



