310 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



ciform plant. Last year I did Dot set any of that order of plants in my 

 garden. But the present year, thinking the bugs had probably left tho 

 premises, I planted my garden with radishes, mustard, and a variety of 

 cabbages. By the first of April the mustard and radishes were largo 

 enough for use, and I discovered that the insect had commenced on 

 them. I began picking them off by hand and tramping them under 

 foot. By that means I have preserved my 434 cabbages, but 1 have 

 visited every one of thorn daily now for four months, finding on them 

 from thirty-five to sixty full grown insects every day, some coupled and 

 some in the act of depositing their eggs. Although many have been 

 hatched in my garden the present season, I have suffered none to come 

 to maturity; and the daily supplies of grown insects that I have been 

 blessed with, are immigrants from some other garden. 



" 'The perfect insect lives through the winter, and is ready to deposit 

 its eggs as early as the 15th of March, or sooner, if it finds any cruci- 

 form plant large enough. They set their eggs on end in two rows, 

 cemented together, mostly on the underside of the leaf, and generally 

 from eleven to twelve in number. In about six days in April — four 

 days in July — there hatches out from these eggs a brood of larva? re- 

 sembling the perfect insect, except in having no wings. This brood 

 immediately begins the work of destruction by piercing and sucking 

 the life-sap from the leaves, and in twelve days they have matured. They 

 are timid, and will run off and hide behind the first leaf stein, or any 

 part of the plant that will answer the purpose. The leaf that they 

 puncture immediately wilts, like the effects of poison, and soon withers. 

 lJalf a dozen grown insects will kill a cabbage in a day. They con- 

 tinue through the summer, and sufficient perfect insects survive the 

 winter to insure a full crop of them for the coming season. 



"'This tribe of insects do not seem liable to the attacks of any of 

 the cannibal races, either in the egg state or at any other stage. Our 

 birds pay no attention to them, neither will the domestic fowls touch 

 them. I have as yet found no way to get clear of them but to pick 

 them off by hand.' n 



NATURAL HISTORY. 



The eggs of the Harlequin Cabbage-bug ("Plate IV, Fig. 2, tf, e) are very 

 beautiful objects. They are about one-twentieth of an inch long by one- 

 thirtieth wide, and are usually deposited in two parallel and closely ap- 

 plied rows of about half a dozen each. When first deposited they are 

 green in color, but soon become white, with black markings. Their re- 

 semblance to miniature white barrels with black hoops is very marked, 

 and the resemblance is heightened by a small black spot in the proper 

 position for a bung hole. The sides of the eggs which are applied to 

 each other are almost entirely black. In oviposition the female moves 

 her ovipositor in a zigzag manner from one row to the other. 



The young larva in hatching cuts out the head of the barrel with its 

 beak with the utmost neatness and precision. At first it is of a uni- 

 form pale-green color, marked with black, and with successive molts 

 takes on certain orange markings. It differs from the adults in the 

 scarcity of orange in its coloration, in the lack of wings, and in having 

 but four joints to their antennae, those of the adult having five joints. 



Under favorable circumstances the rapidity of development of this 

 insect is remarkable. The eggs will hatch on the third day after lay- 

 ing, ami Mr. William R. Howard is authority for the statement that the 

 young bugs will go through all their molts and be ready for reproduc- 

 tion within two weeks. They come early and stay late. In Virginia 



