Fig. 42. A balanced aquarium can be main- 

 tained in a wide mouthed jar. 



or embedded plants. 



5. Keep the aquarium in good light hut avoid 

 direct sunlight. Allow it to stand a few days 

 before any specimens are added. 



6. Remove any uneaten food, dead animals or 

 other debris within twenty-four hours to prevent 

 decay from spoiling the balance. 



7. Keep a glass or screen wire cover over the 

 aquarium to prevent the escape of winged in- 

 sects. As the water evaporates it should be re- 

 placed. 



If you live near a stream a wire "pillow" 

 cage may be used to rear and retain aquat- 

 ic insects. (Fig. 43.) This is particularly 

 useful when working with species which 

 will not develop out of running water. A 

 "pillow" cage is made by bending a sheet 

 of screen wire into the shape of a pillow 

 and fastening the ends and sides together. 

 One end of the cage is weighted so that it 

 will sink and the other end is fastened 

 above water to hold the cage in place. It 

 should be submerged for about one-half 

 to three-quarters of its length. 



Feeding Captive Insects. Insects which 

 obtain their food requirements from plants 

 are sometimes very specific in their tastes 

 and will eat certain plants only. It is al- 

 ways wise to observe what plants the in- 

 sects you wish to rear are feeding upon 

 when taken and try to provide them with 



a continuously fresh supply. Cut plants 

 should have their ends thrust in jars of 

 water in the breeding cages so that they 

 will remain fresh for a longer time. 



Predaceous aquatic species can be fed 

 pieces of raw beef which are suspended on 

 string in the water. These should be re- 

 moved after several hours to prevent spoil- 

 ing the water. Predatory forms like man- 

 ticls, ant lions, beetles, etc., will have to be 

 supplied with living insects. For this pur- 

 pose it is well to culture cockroaches, meal- 

 worms, etc. The latter can be reared in 

 a small crock half filled with breakfast 

 bran to which a slice of apple or banana 

 peel is added occasionally. An ideal food 

 for all chewing insects kept in the labora- 

 tory is given below. Cockroaches can be 

 fed this mixture and cultured for feeding 

 to predaceous species. 



Formula for Chewing Insects. (Taken 

 from Journal of Economic Entomology, 

 Vol. 29, 1936, p. 1026.) 



Corn Flour 4 parts by weight 



Dried Powdered Yeast 1 part by weight 



Skim Milk Powder 2 parts by weight 



Whole Wheat Flour 2 parts by weight 



Wheat Middlings or Bran _ 2 parts by weight 



Honey 1 part by volume 



Glycerine 1 part by volume 



Mix the dry materials and sift out large 

 particles. Mix the liquids and add to the 

 dry ingredients until the right degree of 

 wetness is obtained. This will depend 

 somewhat upon the insects to eat the mix- 

 ture since some species like more moisture 

 than others. A safe procedure is to make 

 it moist enough to hold its shape when 

 rolled in a ball. Feed such balls with 



f*CO T f*LL /t*0 



Fig. 43. A wire pillow cage is used in 

 flowing streams. 



