216 HALF HOURS WITH IN'SECTS. [Packard. 



for example, in New England after the 15th or 20th of May. 

 By early sowing the 3'oung wheat will have got the start of 

 the flies, and too large and strong for them to kill it. 



For a third and often still more destructive insect, which 

 sometimes succeeds in cutting off a half and sometimes 

 nearly the whole of a crop of wheat, oats or barley, we must 

 turn to the very family of parasitic chalcid flies which are 

 as a rule beneficial to agriculture. A few of them make 

 galls in the stems of plants, and the maggots, instead of 

 feeding on the juices of living insects which serve as their 

 hosts, prey on the juices of plants. Such is the famous 

 joint worm or Eurytoma hordei. This is a native insect. 

 It is a little, shining, black, four-winged fl}^, a little over a 

 line in length, with the knees and feet pale yellow. The 

 hind body is attached by a slender pedicel to the thoi-ax, 

 and the male antennae are provided with tufts or verticils of 

 fine hairs. 



When the wheat or barley is about eight or ten inches 

 high, their growth is often checked, the leaves turn j^ellow, 

 and irregular gall-like swellings arise between the second 

 and third joints of the stalk, or in the joint itself. In 

 November, in New England, the worms transform into the 

 pupa state, living through the winter unchanged in the 

 straw, or remaining in the stubble in the field. In Virginia, 

 where the joint worm has been fearfully destructive, the 

 maggot does not transform until late in February, or early 

 in March. From early in May until the first week in July 

 the flies issue from the galls in the dry stubble and are sup- 

 posed to immediately lay their eggs in the stalks of the 

 young wheat or barley plants. 



From a knowledge of the habits of this insect it is evident 

 that the prudent farmer by cooperating with his neighbors 

 can successfully cope with this insect if he and they are 

 careful to burn the stubble in the autumn and spring, and 

 carry on the process for several successive years over a large 



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