194 



Journal of Agricultural Research 



Vol. XV, No. 3 



The adult antennae are much longer proportionately, and this elonga- 

 tion is due mainly to elongation of first and second segments, the first is 

 one- third of the second, the second nearly four times the fourth and nearly 

 twice as long as the third (fig. 4). 



NATURAL ENEMIES 



Among the natural enemies or checks of the species may be counted the 

 gray-damsel bug, Reduviolus ferus (fig. 5), which is a very common and 

 widely distributed species throughout the northern part, at least, of North 

 America, and in fact the holarctic region. Webster and Mally {iSgj, 

 p. 41) states that Coriscus ferus was observed to attack Leptoterma 

 dolobrata L. which was feeding quite abundantly on timothy heads about 

 East Cleveland, Ohio, on June 28, 1896. 







Fig. 4. — Miris dolabratus; A-F, Antennae of nymphs: F, antenna of adult male drawn to same scale 

 and showing relative lengths of segments. (Original.) 



This species has been found in Maine associated with Miris dolabratus 

 as well as with the leafhoppers, and it is probable that it may feed on 

 either with equal avidity. While it has not been seen feeding on the 

 mature M. dolabratus, it is pretty certain that it will feed upon the larvae, 

 as its fondness for leafhoppers in both the nymph and adult stages has 

 been proved by repeated observation. Direct observation of the insects 

 attacked is difficult, as it is almost impossible to follow them in their 

 movements in the field. Even when offered a variety of food in confine- 

 ment it is difficult to determine their selection in the species offered, as 

 they very seldom make their attacks on the insects while under observa- 

 tion, and it is left to infer from the numbers killed how ready they are to 

 prey upon different kinds. We have had them live and thrive in confine- 

 ment and progress to the adult stage on a diet of M. dolabratus and also on 

 a food supply of leafhoppers, and it is probable that they will eat a variety 

 of small insects, the particular kinds being determined rather by the 

 available supply than by any definite choice on the part of the bug. 



They are able to survive considerable periods without food, and their 

 development is doubtless affected either by abundance or scarcity. 



The appearance of the different instars of the early stages is not at 

 all uniform, as individuals of several different stages, as well as adults. 



