LEGUMINOUS CEOFS. 11 



and measures about one-third of an inch across the ex- 

 tended wings. There are three kinds of females. (1) A 

 wingless black one. When examined by a magnifying 

 lens, the head, thorax, and abdomen appear to be fused 

 into one mass. This wingless female is viviparous {i.e., 

 produces living young). (2) A winged viyiparous female, 

 which has a black body, and wings partly yellow and 

 partly green with brown veins. (3) A wingless female 

 which is oviparous {i.e., produces eggs). The oviparous 

 female only appears in the autumn ; and the eggs produced 

 by her are hatched in the following spring. The wingless 

 females produced from these eggs then settle down upon • 

 the young " shoots " of the bean plants, and may cover, 

 in a very short time, a whole crop of beans with their 

 progeny. These insects puncture the bean plants by 

 means of their suckers and extract the juices. This causes 

 a reduced state of vitality, which terminates (if the attack 

 is not stopped) in the failure of the crop. 



Prevention. — (1) To prevent the attacks of the bean 

 aphis, the farmer should carefully remove thistles, curled 

 dock, £orse, and other wild plants on which the insect is 

 found. (2) To produce a healthy and vigorous growth 

 by the judicious use of manures. A good system of culti- 

 vation is always a means of lessening the attacks of this 

 insect. 



Cure. — (1) As soon as the " plague " makes its appear- 

 ance, cut oif all the infested " tops " and burn them. (2) 

 Where the crops are on a small scale, soot or soap-suds 

 are means of getting rid of the bean aphis. (3) Manuring 

 the land with a top-dressing of iron sulphate (| cwt. per 

 acre) has a tendency to produce a luxuriant growth ; and 

 after this treatment the plants are rarely attacked by 

 this injurious insect. 



