VEGETABLES DESCRIPTION AND CULTURE. 263 



size at a and at b, magnified several times. Figure 72 

 shows the way in which the insects work upon the young 

 plant. In figure 73 the perfect insect is given, the natural 

 size of which is indicated by the cross lines, and in the same 

 figure the magnified pupa or chrysalis 

 is shown at d, and the actual size at c. 



These insects increase so rapidly that 

 unless destroyed at their first appear- 

 ance, which is shown by the leaves 

 drooping and turning yellow, it is al- 

 most impossible to eradicate them. 

 Such plants should be at once pulled up, 

 and with the soil in which they grew, 

 burned, which will prevent their in- 

 crease. Applications of soot or salt upon 

 the beds, of lime-water, stale urine, and tobacco water, are 

 also employed, and beds strewn with fine charcoal are said 

 to be less liable to attack. It is difficult, how T ever, to reach 

 the insect, except by pulling up the bulb. It is said that 



removing the earth from the onion bulbs as soon as growth 

 has well commenced will prevent the fly from depositing 

 its eggs, and the onion, being nourished by its fibrous 

 roots, ripens and keeps better. 



To preserve them. — Pull them on a dry day, dry them 

 thoroughly in the shade, and stow them in a loft where 



