336 Phylum Arthropoda 



chimney is placed against that of the box, the hanging-fly will drop into 

 the container. 



Not more than twenty or thirty specimens should be placed at one 

 time in a prison box of this size, for there is danger that the flies will 

 entangle their long legs with those of the other flies. 



Individual Cages. The ordinary Mason glass fruit jar was found to 

 be a very satisfactory cage for an individual or a single pair of hanging- 

 flies. The jar must be furnished with a twig of buck-brush, or of some 

 other woody plant, to serve as a support from which the insect may 

 suspend itself. The opening may be closed with a small piece of cheese- 

 cloth fastened in place by a rubber band. All jars should be kept in a 

 shady part of the laboratory and preferably upon the floor or upon low 

 stools, in order to make conditions as nearly natural as possible. 



Such cages I have found advantageous for the following reasons: 

 (1) they are convenient to handle; (2) the hanging-flies seem satisfied 

 in this sort of a cage; (3) the insects may easily be transferred from 

 one jar to another; (4) the eggs may be collected readily by inverting 

 the jar; and (5) small flies and other insects placed in the jar for food 

 cannot escape. 



Care of the Immature Stages. The most convenient containers for 

 keeping the hanging-fly eggs are small or medium sized clay flower pot 

 saucers lined with moist, white cellu-cotton over each of which the 

 flower pot itself is inverted. By adding a small amount of water each 

 day to the cellu-cotton, the eggs may be kept moist. 



After hatching, each larva should be transferred to a similar container, 

 that differs only in having a little pile of about a tablespoonful of rich 

 garden soil upon the cellu-cotton. Moisture and tiny pieces of beef 

 steak must be provided daily on the cellu-cotton near the soil. 



When the larvae enter the soil to pupate, less moisture should be pro- 

 vided, but by no means should the soil be allowed to dry out. 



Order trichoptera 



ON REARING TRIAENODES* 



CADDISWORMS of this genus are common in beds of the water- 

 weed Elodea. They swim freely about, carrying their slender, 

 spirally-wound cases with them. They eat plant tissues, especially 

 Elodea, and are easily maintained in aquaria, even in tap water, and 

 at all seasons. When grown they attach their cases lengthwise to the 

 stems or to other solid support for pupation. The pupal stage lasts 7 

 to 12 days. When ready for final transformation the pupa leaves its 



* Abstracted from a thesis by Wynne E. Caird in the Cornell University Library. 



