BULLETIN NUMBER 23, DECEMBER, 1893. 



85 



Fig. 15.—Mur<jantia liistrionica, im- 

 ago wicli wiQfjs closed and with 

 wings expanded. 



24 hours, leaves nothing to be desired, and thousands of doUars are 

 vearlv saved to small growers who most need the assistance." (^Insect 

 n/eVv, 13.) 



HARLEQUIN CABBAGE BUG. 



(Murgantia histrionica Hahu.) 

 This I haye found to be one of the most destructive insects to cabbages 

 in certain parts of Maryland, and it has been particularly abundant dur- 

 ing the last two or three years. Known in the Southern States as the 

 Harlequin Cabbage Bug or the Calico Back,this insect has been gradually 

 spreading from the extreme Southwest to the North and East for the 

 past twenty vears, and has only recently become a serious trouble in 

 Maryland. The adult bugs (Figure 15,) hibernate under old grass, 

 stones, logs, and other rubbish, and upon the advent of spring take to 



the first cruciferous plants that put forth 

 leaf, and lay their little barrel-shaped 

 eggs. (Figure 16 <:) in small clusters on 

 the undersides of the leaves. There are 

 several generations in the course of the 

 summer and wherever the insect becomes 

 abundant the crop is generally ruined. 

 The in sect 'feeds upon the cabl)age in all stages of growth, not by gnaw- 

 ing the leaves, but by puncturing them with its beak, causing the leaves 

 to wilt by exhaustion of the juices. 



This is a very difficult insect to deal with, as the older remedies have 

 not proved efficacious. My early recommendations in treating of this in- 

 sect, of clean culture, raking up and burning all rubbish in autumn and 

 hand-picking the bugs on the first opportunity in spring, were, on the 

 Avhole, the most available remedies in our possession up to last spa'ing. 

 In 1892, however. Prof. H. E. AVeed, of the Mississippi Agricultural Ex- 

 periment Station, who has had excellent opportunities of studying and 

 experimenting with this insect, because of its great abundance in his 

 locality, found that the following plan was satisfactory, and it may well 

 be adopted by Maryland cabbage growers. Wild Mustard is one of the 

 earliest cruciferous plants to appear in spring, and the hibernated bugs 

 take their first spring meals on this plant. They seem to prefer it, in 

 fact, when young and tender,to cabbage. Mr. Weed at first (1891) killed 



tlie bugs upon the mustard when- 

 ever he found them, by sprinkling 

 them with pure kerosene, but the 

 following year he decided to sow a 

 row or two of mustard between the 

 prospective rows of cabbages. It re- 

 sulted from this that the great ma- 

 ioritv of the hibernated bugs of the 

 vicinity clustered upon these early bastard plants, and were killed by tne 

 application of pure kerosene, to the almost perfect protection of the cab- 



Fig. IG.— Murgantia hMrinnica: a, larva 

 b, pupa; c ' eggs:ci eggs enlarged, side view; 

 f, same, t p view 



