10 The Bulletin. 



flew away to find a mate and tlien do its share in stinging other lice. 

 An insect which grows to its maturity inside the body of another in 

 this way is known as a true internal parasite, and the insect which 

 falls victim to it is a parasitized insect. One may find many parasitized 

 lice on cabbage and other crops. 



Among the colonies of cabbage lice one may often find some small 

 beetles of yellowish color with black spots and markings. These are 

 "Lady beetles" and they are there for the purpose of eating the lice, 

 so they are beneficial and should be given encouragement. The lady 

 beetles lay eggs which hatch to little bluish colored worms (larvae) with 

 yellow spots, — these little worms (larvse) have legs and are quite active, 

 running about over the cabbage and eating a great many of the lice. 

 There are several distinct kinds of lady beetles that devour the cabbage 

 lous.e. 



Also one may find among the cabbage lice small worms, more or less 

 snail-like in shape, which do not have legs. These are larger at the tail 

 end and when feeding they swing the pointed head end about from side 

 to side. When this pointed head end strikes a louse the louse is seized j 

 by a pair of very small pointed jaws and held fast while the worm sucks 

 tlie louse dry and then the empty skin is cast off. Often the worm re- ' 

 mains motionless for a long time. These worms are the maggot stage 

 (larvae) of what are known as "Syrphus Flies," and they are beneficial ' 

 in that they destroy the cabbage louse. The adult parent Syrphus flies 

 are yellow-and-black, two-winged flies and are often seen on flowers or ] 

 hovering in the air near them. | 



So far as we know there are no other important enemies of the cabbage i 

 louse. Parasites, lady beetles and the Syrphus flies are their principal 

 natural enemies. While we should know of these helpful insects and 

 should encourage them all we can, yet we must not depend on them, for 

 while they do perhaps prevent the lice from becoming as destructive as i 

 they otherwise would, yet when the lice are once present in great num- i 

 hers, these natural enemies are not sufficient to prevent damage. \ 



REMEDIES. i 



There are several different remedies that can be used against the ; 



cabbage louse, as well as several methods of prevention. j 



Preventive Measures. — In the first place the louse will be less likely ] 



to become destructive if all weeds are kept down, especially such weeds , 



or seeding plants as are related to cabbage. Do not allow mustard i 



or turnip plants to grow up or go to seed in the spring near the cabbage, , 



as they give a harboring place for lice. Then again, remember that the j 



lice may be on the rough outer leaves that are left on the stem when I 

 the head is cut for inarket, so it is important to destroy all remnants as 

 fast as the heads are cut. These measures will help to keep the lice 



from becoming numerous. I 



Soap Solution. — In our own experience this is the best and most ' 



practical remedy for the cabbage louse. We have used it with entire 1 



satisfaction, prepared in this way : Take any ordinary brand of laundry j 

 (or home made) soap, shave it into thin pieces in water at the rate of ^ 



1 



