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JOURNAL OP ECONOMIC ENTOMOLOGY 



[Vol. 2 



by Sir John Lubbock on pages 2 and 3 of his classic work.^ This 

 consists essentially of two glass plates, containing between them a 

 laj^er of pulverized earth in M^hich the ants may burrow at their 

 pleasure. C'Onsiderable difficulty was experienced in getting the 

 glass plates the proper distance apart : if too for apart the ants could 

 make burrows which were not open to observation and if too close 

 together insufficient room was afforded the queen in which to stand 

 and walk upright. As the queen is about twice as tall as the worker 

 it seemed for a time that a suitable cage could not be constructed. 



Fig. 1.— Artificial formicary or cage used iu studying the Argentine ant : 1, 

 supporting platform ; 2, standard ; 3, cage proper, made of glass and leather, 

 containing earth; 4, base; 5, cover. 



After repeated trials, however, it was found that if the space be- 

 tween the glass plates were made exactly 1.75 mm. the queen would 

 have sufficient room and the workers could not construct invisible 

 galleries. 



This type of cage and its supporting stand are well illustrated by 

 Figures 1 and 2. Figure 1 shows the several parts of the cage ; " 3 '.' 

 is the cage proper, consisting of two plates of glass held uniformly 

 1.75 mm. apart by strips of leather at all four edges, a door or open- 

 ing being left at one corner (See Figure 3). Old negatives, the 

 films removed with caustic soda, have been found the most desirable 

 for making these cages, both because such glass is remarkably clear and 

 free from imperfections and because it is of uniform thickness. The 



^Avebury. — "Ants, Bees and Wasps," 1881. 



