176 



FIRST LHSSONS IN ZOOLOGY 



each lay one or a few eggs, which usually last through 

 the winter, new "stem mothers" hatching from them 

 the following spring. When the aphids get too crowded 

 on a plant or tree some winged individuals are produced 



Fig. 133. — Moths of the peach-tree borer, Sn}ini}wi(/cn cxit/osa, natural size; 

 the iipperone and the one at the right are females. (I'hotograph b}' j\I. 

 \. Slingerland.) 



which can fly to another food-plant and establish a new 

 colony. 



It will almost certainl)' be noted during the course of 

 observing that the aphids are visited by ants (fig. I 35), and 

 by careful watching it may be seen that these ants lick up 

 the sweet honey-dew secreted by the aphids. So much 

 do tlic ants like this honey-dew that sometimes they take 

 special care of a colon)' of aphids, driving away their 

 enemies, and visiting them regular!)- to feed. Aphids 

 have been called the cattle of the ants. 



