August, '21] HAMILTON: BOX MIDGE CONTROL 359 



NOTES ON THE LIFE HISTORY AND THE CONTROL 

 METHODS OF THE BOX WOOD LEAF MIDGE, 



{Monarthropalpus buxi Labon.y 



By C. C. Hamilton, College Park, Md. 



The Box Wood Leaf Midge is a small, frail, yellow Cecidomyid, the 

 immature stages of which are found in the leaves of box wood plants. 

 Here it causes jharacteristic gall-like swellings (pi. 4, fig. 3) and in cases of 

 severe infestations the dropping )f the leaves, results in a ragged and 

 unsightly bush or hedge. This pest was apparently introduced from 

 France or Holland in imported box wood plants. Felt in 1910 records 

 its first appearance in the United States at Kingston, R. I. Since -then 

 it has been reported from a number of states along the Atlantic coast 

 and from California. 



It is the purpose of this paper to give a summ.ary of the most impor- 

 tant phases in the life history of the insect and some of the more prom • 

 ising methods for controlling it. 



Life History and Biology 



In the vicinity of Baltimore, Mar^dand, the insect passes the winter 

 as a partly grown larva, molting at least once in the spring before pu- 

 pating. Pupation commences about the first of May and continues 

 until the latter part of the month, the majority of the larvae pupating 

 from the 8th to the 12th. The pupal stage lasts from two to three 

 weeks with an average of sixteen or seventeen days. When ready to 

 emerge the pupa pushes its way through the lower surface of the leaf 

 until all but the last five or six abdominal segments are out. It then 

 crowds the body forward in the pupal skin until the skin splits along 

 the dorso median line of the thorax. From five to ten minutes are re- 

 quired for the adult to emerge from the pupal skin with an additional 

 two to five minutes before the wings have expanded and the adult 

 is able to fly away. It is in this period, from, the breaking of the leaf 



'Contribution from the Entomological Laboratory Maryland Agricultural Ex- 

 periment Station - December 20, 1920. 



