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structed to facilitate keeping the soil in the bottom of the cage moist 

 without pouring water in from above, which would cause packing. It 

 is of zinc, and so arranged that a pan surrounds the perforated com- 

 partment for the earth, thus allowing the water poured into the pan 

 to penetrate the perforations and moisten the earth in the breeding- 

 cage gradually and without the disadvantages alluded to. The box 

 proper or central portion has a swinging door, the other three sides 

 being of glass, or one or more of them may be covered with gauze to 

 give ventilation. The top is covered with wire gauze. This cage 

 admits abundant light and air, and is easily opened for the removal 

 of specimens, the insertion of fresh food, etc. 



756. THE MUSLIN- COVERED BREEDING CAGE. 



This apparatus is useful in the breeding and study of the habits of 

 insects affecting small grains and forage plants, and is applicable to 

 both indoor and outdoor experimentation. It consists of a strong box 

 for the reception of the earth in which the plants to be studied are 

 propagated, and of a light frame covered with gauze, which at the 

 proper time may be fitted closely over the growing plants to retain 

 the insects that have been introduced or to protect the plants from 

 undesirable species. The one exhibited is of small size, and larger 

 boxes will ordinarily be more convenient, while for field work the box 

 with the growing plant may be embedded in the soil, or the screen 

 alone may be used to cover a portion of naturally growing vegetation. 



757. THE ROOT CAGE. 



This apparatus was devised for the study of insects affecting the 

 roots of plants, and consists of a zinc frame with two plates of glass in 

 a vertical position, with an arrangement for a zinc sliding cover which 

 fits into grooves, and may be removed to admit of examination of the 

 progress of the root-infesting insects. The cage exhibited is of small 

 size, but in the Avork of the Entomologist cages of various sizes are 

 used, some being very large to admit of the reception of small shrubs. 



758. PENT-HOUSE BREEDING CAGE. 



This is exhibited to illustrate a simple method of constructing a cage 

 for the breeding of insects which feed on low plants, or for use in the 

 field on collecting excursions. It is constructed by cutting two flexi- 

 ble twigs and bending them into the shape of two arches, patting one 

 over the other at right angles and pushing the ends well into the 

 ground. Over the pent-house thus formed a piece of gauze is stretched 

 and the cage is complete. 



759. THE AERIAL BREEDING CAGB, OR BAG. 



A simple device for the outdoor rearing of species which oviposit on 

 trees and large shrubs is frhown in this exhibit. It is valuable tor 



