236 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, 1891. 



and hatches in the spring into a little wingless creature like the one 

 in the slide now before you. This minute insect sticks its proboscis 

 into the bark and begins f eeding on the juice. It grows rapidly, and 

 after molting its skin several times, it lays a number of eggs, each of 

 which develops into a little wingless creature like its mother. These 

 second generations of so-called females have exactly the same habits 

 as their mother, and soon lay a large number of eggs. This process 

 goes on all through the warmer portion of the year, innumerable 

 multitudes of the little wingless females being in this way 'produced and 

 the result is that a tree which is once attacked rapidly becomes infested. 

 These little wingless females crawl all over the branches and roots, and 

 wherever they settle they raise the characteristic galls which I have just 

 shown to you, so that the whole tree becomes knotted and distorted and 

 weakened to such an extent that it is quite incapable of bearing fruit. 

 All through the summer the insect, not possessing wings, is only able 

 to crawl slowly along, and does not spread to any great distance except 

 when carried by accidental agencies, such as birds or high wind, from 

 one tree to another. With the first cold of autumn, however, the esrs:s 

 of the little wingless females produce winged females which fly from 

 tree to tree, and thus carry infection to considerable distances. They 

 then settle down and produce the wingless males and females 

 by which the winter eggs are produced. With regard to remedies 

 for this insect, spraying and washing affected trees with kerosine 

 emulsions and caustic washes has been found to a certain extent 

 successful, and when properly applied these washes undoubtedly kill 

 the insect wherever they touch it. Though the difficulty in getting 

 at the roots and crevices between the branches is so great that many 

 people are of opinion that once a tree is affected the best thing is to 

 cut it down and bum it to prevent its becoming a centre of infection, 

 On the whole, however, there is every reason to hope that as the 

 insect is only able to fly for a short time in the year, much may be 

 done by planting lines of trees to serve as wind breaks and prevent 

 the blight from being carried from one orchard to another, and also 

 by keeping a sharp look out in the spring and destroying with 

 kerosine oil emulsion or by caustic washes, any small colonies that 

 may have arisen from the offspring of winged individuals that have 

 been blown across from affected orchards in the preceding autumn. 



