BIONOMICS OF THE CHINCH BUG. 3 



determined, but apparently it is during the month of April. Mi- 

 gration is governed largely by seasonal conditions. The phenomenon 

 of migration in this insect in spring on such an extended scale is a 

 topic for general conversation among the planters in regions subject 

 to infestation. The planters state that during migration the bugs 

 fill the air like swarms of bees and are even known to enter dwellings 

 at night. To a lesser extent the adults spread on foot to grain fields 

 from their winter quarters, especially when such fields are not far 

 removed from where the bugs have hibernated. It is not an uncom- 

 mon practice in the South to sow grain, especially winter oats, on 

 corn stubble land, and in such cases the adults find their food without 

 having to search for it. There does not appear to be any definite 

 summer migration. This may be due partly to the fact that a large 

 number of the individuals of the summer generation are short-winged 

 forms, unable to fly, and hence are compelled to seek fresh fields by 

 crawling to them. 



BEHAVIOR. 



Adult chinch bugs often feign death when disturbed, especially 

 when they happen to be lying on their backs. When it is least ex- 

 pected, however, they will right themselves quickly and scamper away 

 to seek concealment under the nearest shelter, and are then difficult to 

 capture. They are exceedingly quick on their feet, and when a vial, 

 in which they are held captive, is opened, are often able to regain 

 their freedom before the observer realizes what has happened. When 

 adults are captured in the field they frequently escape by crawling 

 through the little spaces between one's fingers and quickly drop to 

 the ground. The nymphs of all stages are quite as active as the adults 

 and often escape from captivity in a similar manner. Activity, of 

 course, depends upon prevailing temperatures. Early in the morning 

 the adults and nymphs are often quite sluggish and are easily taken, 

 but by the middle of the day they become exceedingly active. 



This insect is a sociable creature, both in its nymphal and adult 

 stages, and when a number of individuals are placed in the same cage 

 they will be found, later on, feeding in a little group. When disturbed 

 they scamper in all directions, to reassemble when danger has passed. 

 Upon removal of the lid from a tin ointment box used as an incuba- 

 tion cage the nymphs that had hatched were often found huddled 

 closely together in a little group along the edge on the underside 

 of the lid, these nymphs being very small when newly emerged. 



MATING. 



Mating takes place repeatedly among the individuals of this 

 species, and may occur at intervals of from 5 to 8 days. The adults 

 remain in copula for some time, occasionally for 12 hours or more. 



