STRAWBERRY INSECTS 367 



breaks have been reported from Missouri, Illinois, Indiana and 

 ('anada. 



The adult is a black-bodied, four-winged fiy about } inch 

 in length and has a row of whitish spots on each side of the 

 abdomen. The flies emerge from the ground in early spring 

 and the female inserts her pure white, elongate, compressed 

 eggs in the petioles of the leaves. The eggs hatch in about two 

 weeks and the yellowish or greenish larvae attract attention in 

 May by eating small rountl holes in the leaves. When al^undant 

 they may completely destroy the foliage in a few days. Much 

 of the feeding is done at night ; during the day the larvae remain 

 curled up on the underside of the leaves or hide at the base of 

 the plant. They become full-grown by the last of June in 

 Illinois and are then about | inch in length, pale greenish to 

 grayish-yellow in color ; the head is yellow, marked with at 

 least three large dark spots. When mature the larva enters 

 the ground and constructs an oval cocoon composed of earth 

 cemented together with a gummy substance within which it 

 passes the winter as a shortened, thickened larva, the so-called 

 pre-pupa. Pupation takes place in early spring and the adults 

 emerge soon after. 



As a rule, there is only one generation a year, but there is 

 evidence to show that occasionally a partial second brood may 

 develop in the more southern part of the insect's range. 



Means of control. 



The sawfly larvae are readily killed with arsenicals, and if the 

 application is made before the fruit is more than one half grown, 

 they may be used with perfect safety. Paris green, 1 pound in 150 

 gallons of water, with the addition of three pounds of fresh lime, 

 has given good results, but as there has been some complaint of 

 burning of the foliage with this poison, arsenate of lead, 4 pounds 

 in 100 gallons of water, will probably be found more satisfactory. 

 It should be used at the first appearance of the larvae, before 

 the berries are more than one half grown. After the fruit has 

 begun to ripen use hellebore, 4 ounces in 2 gallons of water. 



