The Bulletin. 21 



The Harlequin Bug sucks the sap from the plant, it does not eat the 

 leaves. It is evident, therefore, that a poison like paris green (which 

 remains on the surface of the leaves), is of no use whatever as a remedy 

 for it. The farmer might literally cover the surface of the leaf with a 

 layer of paris green and yet this pest (by thrusting its beak through 

 into the plant and sucking out the sap), would still thrive as if no effort 

 had been made to check it. In fact, it could not eat paris green even if 

 it wanted to. Like the cabbage louse, it is a sucking insect. 



Natural Enemies.- — Many kinds of injurious insects are preyed upon 

 by birds, moles, toads, or even by other insects, but the Harlequin Bug 

 has very few such enemies, and this is probably because of a peculiar 

 odor and taste, for it belong to the "stink bug" family of insects (Order 

 Hemiptera, Family Pentatomidw), many of which possess extremely 

 strong and nauseating odors. JSTevertheless the English sparrow seems to 

 destroy some of the Harlequin Bugs. At Eed Springs, in Robeson County, 

 Mr. W. M. Roberts says that the English sparrow is quite an efficient aid 

 in keeping it in check, and that in consequence the damage by the 

 bug is often not serious. Others have made mention of this same useful 

 habit of the English sparrow. But as a rule the Harlequin Bug is 

 fairly exempt from enemies. 



But while the insects themselves are thus comparatively free from 

 attack, the eggs are not. There is a very small, black, four-winged in- 

 sect, more or less similar to a very small wasp, which lays its eggs 

 within the eggs of the Harlequin Bug. This is shown in Fig. 7. The 

 egg^ of this little insect hatches to a grub, which comes to full maturity 

 inside the egg of the Harlequin Bug, — when matured this little grub 

 emerges as a tiny four-winged fly like that which laid the egg. This 

 tiny insect is therefore a parasite in the egg, of the Harlequin Bug, and 

 is known as an egg-parasite. Sometimes these are abundant enough to 

 do real good. In 1903 the writer bred parasites from a small lot of 

 eggs indicating a parasitism of not less than 33 per cent. At other times 

 they are so scarce as to be of no real importance. 



The young bugs are sometimes attacked by what is known as the 

 ''wheel bug," according to Mr. Chittenden, but the good done by these 

 is not great. By far the most useful natural enemy is the egg-parasite 

 already referred to. 



remedies. 



We have seen that the Harlequin Bug sucks the sap from the plant 

 which it attacks, and that therefore poisons like Paris green are use- 

 less against it. There seems also to be only limited opportunity for the 

 use of the contact insecticides like kerosene emulsion, and we are there- 

 fore forced to depend largely on indirect methods of preventing their 

 ajjpearance, or tedious labor after they appear. 



Trap Crops. — The proper use of trap crops constitutes one of the best 

 methods for the grower who wishes to raise early cabbage and collards. 

 A few rows of early mustard may be sown betAveen where the rows of 

 cabbages or collards are to be set. This will get an early start and will 

 be large enough to attract the bugs before the cabbage is set, and as the 



