278 



INJURIOUS INSECTS AND FUNGI. 



[Dec. 1896. 



forth living larvae, is dark brown, having large wings with 

 black veins ; the cubital vein, as pointed out by Mr. Buckton,, 

 has a single furcation, or fork, differing in this respect from 

 other tribes of the Aphididce. Towards the end of the summer, 

 among the larva? produced by the winged females are wingless 

 egg-bearing females, of a dirty yellow colour, without beaks or 

 rostra, and therefore unable to feed. Only one very small, 

 round, transparent egg is laid by each of these wingless females, 

 and is deposited in the crevices of the bark. Propagation — the 

 regular continuity of existence — is principally carried on, how- 

 ever, by the hibernating viviparous larva?, which pass the winter 

 wrapped in their woolly coats upon the trunks of the trees, 

 on the branches and twigs, as well as upon the roots. These 

 wingless females are woolly, of a brown colour, and broad or 

 squat in shape (Fig. 2). The larvae from these are at first 

 rather lighter in colour, and after a time emit wreaths of 

 woolly material from their dorsal pores, and become completely 

 covered, so that a group of them has the appearance of a piece 

 of cotton wool (Fig. 2). In their early stages the larvae have 

 enormously long beaks or rostra, bent underneath the body, 

 and extending much beyond the extremity of the body, so that 

 they appear to have tails when seen without a microscope. 



There is no visible difference between the generations of this 

 insect that are found upon the branches and those on the roots 

 of apple trees. 



Methods of Prevention and Rem edies. 



Apple trees should be kept free from mossy and lichenous; 

 growths which serve as shelters for woolly aphides, as well as 

 for many other injurious insects. Lichens and mosses can be 

 killed by throwing finely powdered lime over the trees during 

 the winter, in foggy or damp weather, so that the lime adheres 

 to the trees. This can be done by men with tin scoops, li/ke 

 flour scoops, fastened to the ends of long poles. Sulphate of 

 iron dissolved in water, at the rate of 1 lb. to 1 gallon of water, 

 sprayed over the trees in winter by means of a powerful garden- 

 engine, or hop-washer, will kill lichens and mosses, and interfere 

 much with the Woolly Aphis. 



Young trees should be carefully and systematically pruned, so 

 that their boughs do not intertwine, and plenty of air and 

 light is admitted. Periodical, search should be made for woolly- 

 aphides and other insects upon young trees. When the Woolly 

 Aphis is discovered in wounds and scars on the stems and 

 branches, which are often frequented by its colonies, these 

 places should be treated in the late autumn or winter with a thick 

 compound of soft soap and paraffin oil, mixed in the proportions 

 of 3 gallons of paraffin to 2 lbs. of soft soap and 25 gallons of 

 water, worked into the cracks and scars with a stiff brush. 

 Infested boughs and twigs should be syringed at the same 

 period with a mixture of 5 or 6 lbs. of soft soap and 5 gallons of 



