136 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8 



In working out the complete life cycles the following general types 

 of cages have been thoroughly tested with more or less satisfaction. 

 1. Ordinary standard size flower pots, 12, 15, and 16 inches respec- 

 tively in diameter and depth. Red pots have proven more satisfactory 

 than others for they do not crack and scale so badly from freezing and 

 thawing (Plate 3, figs. 2 and 4). 2. Cyhnder-shaped cages 20 inches 

 in diameter and 4 feet deep, constructed of 18- and 20-mesh brass 

 and bronze wire cloth, buried their entire depth and covered with a 

 cone-shaped wire top. 3. Cylinder-shaped cans, 20 inches in diam- 

 eter and 2 J feet deep, made of galvanized iron with openings at the 

 bottom for drainage. 4. Cylinder-shaped cans as No. 3 but with 4 

 square feet of 18- or 20-mesh brass or bronze cloth on sides, and the 

 bottom of the same material. 5. Cylinder-shaped cages entirely of 

 18-mesh galvanized wire cloth (Gilbert and Bennett's ''Pearl" wire) 

 20 inches in diameter and 2^ feet deep, buried their entire depth, as 

 the others, and covered with cone-shaped wire covers (PI. 3, fig. 1). 

 6. Cylinder-shaped cages as No. 5 with an outer casing of heavy 6- 

 mesh galvanized screen. (PL 3, fig. 3.) 7. Cages constructed of 

 20-inch tile, one and two tile deep and covered at the bottom with a 

 durable wire screen. 8. Rectangular-shaped cages 5x8 feet in width 

 and length, 2J feet deep below ground and 2J feet above ground, con- 

 structed of metal and wooden frames covered with 18-mesh pearl wire 

 cloth (PI. 4, fig. 5).i 



Coleopterous larvae with a three-year life-cycle were bred in all of 

 the cages from egg to adult. Type No. 2 has been discarded since 

 the galvanized wire will last sufficiently long and is not nearly so 

 expensive as the brass or bronze cloth, and it has been definitely 

 decided that cages need not be over 2 J feet deep, at the most. The 

 tile cages (No. 7) were no more satisfactory than the flower pots and 

 were quite difficult to examine. Cages 5 and 6 were quite satisfactory 

 but they were no more so than the flower pot cages and since they are 

 considerably more expensive, they will hereafter be replaced largely 

 by the latter. Cages 3 and 4 are somewhat cheaper than 5 and 6 and 

 about as satisfactory but will be replaced hereafter by pot cages, for 

 the reason just given. The large rectangular cages (No. 8) are quite 

 satisfactory and are used to serve as checks on the smaller cages. 

 Usually several species of the same genus are placed in each of these. 



As already intimated, the flower pot cages, taking everything into 

 consideration, are the most satisfactory, are easily handled, cheap, and 

 well suited for underground insects. The pots are filled with good soil 



1 Cages of this style may be used for a double purpose, first as breeding cages for 

 underground insects, and second for studying the seasonal life-history of aerial 

 insects, such as the army worm {Heliophila unipuncta) as was done at Lafayette the 

 past year. 



