GREEN-FLIES AND PLANT-LICE 325 



them either underground or in specially constructed 

 chambers, where they can gain ready access to them and 

 " milk " them for honey-dew. There has been a certain 

 amount of exaggeration in the description of these facts 

 by some of the older writers ; but it is undoubtedly true 

 that some species of ants keep special flocks or herds of 

 aphides, and feed on their sweet secretion. 



Other small insects nourish themselves on the enor- 

 mous swarms of plant-lice in a less gentle way, but a way 

 which man is very glad to see in active operation, namely, 

 by biting them and sucking out their soft entrails thus 

 destroying them in great numbers. The lady-bird beetle 

 is especially active in this matter, both when it is a grub 

 and on attaining its adult form. A trustworthy observer 

 saw as many as forty aphides consumed by a lady-bird in 

 an hour. Where the plant-lice or aphides abound, there 

 come also in countless swarms the beetles known as 

 lady-birds. In the year 1869, such a cloud of these 

 beetles passed over and settled on the fields and gardens 

 of Kent, Sussex, and Surrey, as to cause something like 

 terror; it was impossible to walk in the lanes without 

 crushing hundreds under foot. But the little lady-birds 

 are not like the terrible locust, which appears in millions 

 and devours all vegetation before it ; on the contrary, 

 they are what are called " beneficials," and come solely to 

 feed on and destroy the plant-lice of the hops, plum trees, 

 and apple trees. A first-rate hop crop in the year 1870 

 was the consequence of the abundance of lady-birds in 

 1869. It is this beneficent activity of the lady-birds which 

 has given them their name. In Italy they are called 

 Bestioline del Signore, also Madonnine, and Marioline, and 

 in France Bete a Dieu. In English they are " our lady's 

 blessed bugs," which save the crops from destruction. 



The exertions of the aphides in pricking the plants 

 they infest so as to get at their juices lead to the 



