April, '17] SMITH: MEALY-BUG PARASITE 267 



a layer of potatoes and the interspaces filled with moistened sand. 

 These trays are put in a warm dark place and sprouting occurs in a 

 short time. Mealy-bugs are then introduced and breeding takes place 

 very rapidly. These trays are made so that they will fit interchange- 

 ably in the breeding cages. In order to supply new host material in 

 any breeding cage, it is only necessary to place the older tray on the 

 lower shelf, with the fresh tray above. In this way all the parasites 

 which may occur on the old tray as young larvae or pupae within the 

 mealy-bugs are retained. This process of shifting the trays downward 

 as each fresh tray is added, is continued until all parasites have reached 

 maturity, when the older material is discarded. By this method we 

 have been able to take thousands of adult parasites daily from the 

 breeding cages for liberation in the orchards. 



Handling and Shipment of Parasites for Colonization 

 The adults are collected from the cloth walls and top of the cage by 

 use of a glass cylinder about two inches in diameter and eight inches 

 long. This is provided with a cork at one end into which is inserted a 

 short piece of 8 mm. glass tubing. This tube projects through the 

 cork on the inside of the glass' cylinder in such a way as to prevent the 

 escape of the captured parasites. The cylinder itself is lightly filled 

 with finely shredded paper upon which the parasites may rest. They 

 are shipped or taken in person to the field colonies in these cylinders. 

 When shipped by mail the cylinder is wrapped in moist sphagnum 

 moss and this is then packed in a pasteboard box in its entirety. 

 The method is very satisfactory for shipment within the state, but 

 when sent to points outside the infested mealy-bugs themselves are 

 forwarded, since the adult parasites do not survive a long hard journey. 

 When colonizing the parasites in the orchard the cylinder is usually 

 tied horizontally in a crotch of the tree and both corks removed. This 

 prevents injury from storms. Where possible, not less than five to 

 ten thousand are placed in a single colony. 



Present Distribution 

 This parasite has been distributed pretty thoroughly throughout 

 the mealy-bug infested sections of the state and has become established 

 in practically every colony. The principal regions are the counties of 

 Los Angeles, San Diego, Ventura, Santa Barbara, and Yuba, the latter 

 in the northern part of the state, the former all south of the Tehachapi 

 mountains. The species has also been sent to the Hawaiian Islands 

 and to Florida. 



Economic Importance of Paraleptomastix abnormis 

 There are at least two important general requirements which a para- 

 site must fulfill if it is to become of value in the control of its host and 



