282 Missouri Agricultural Report. 



shown by the following list of vegetable food found in the northern 

 flickers examined : 



The services which Flickers render in destroying the ground-in- 

 Tiabiting ants may be better appreciated by looking carefully into the 

 relationship existing between ants and the destructive plant-lice with 

 which their lives are curiously associated. The world-known scientist, 

 Professor Comstock, in his "Manual of the Study of Insects," says: 



"It is easy to see what benefit ants derive from this association with 

 plant-lice, and how they should learn that it is w^orth while for them to 

 ■care for their herds of honey-producing cattle. Little has been done, 

 however, to point out the great benefit that accrues to the plant-lice from 

 this relationship. It seems fair to assume that the plant-lice are greatly 

 benefited, else why has the highly specialized apparatus for producing the 

 honey-dew been developed? 



"Writers long ago show^ed that ants protected plant-lice by driving 

 away from them lady-bugs and other enemies. Recently, however, Pro- 

 fessor Forbes has demonstrated that, in certain cases at least, a more 

 important service is rendered. In his studies of the corn plant-louse he 

 found that this species winters in the wingless, agamic form in the earth 

 of previously infested corn fields, and that in the spring the plant-lice 

 are strictly dependent upon a species of ant, Lasius alienus, which mines 

 along the principal roots of the corn, collects the plant-lice, and con- 

 veys them into these burrows, and there watches and protects them. 

 IVithout the aid of these ants the plant-lice were unable to reach the 

 roots of the corn. On page 631 it is stated: 'Ants take very good care 

 of their cattle (aphids), and will carry them to new pastures if the old 

 ones dry up. They also carry the aphid-eggs into their nest and keep 

 them sheltered during the winter, and then carry the young plant lice 

 out and put them on plants in the spring.' " 



Mr. William Dutcher, president of the National Association of Au- 

 dubon Societies, writes : "If the Flicker had no other valuable economic 

 quality, it would deserve protection because it is an enemy of the ant 

 family. " 



