34 
IMPORTANT AND FAMILIAR INSECTS 
hawk, butcher bird, and great-crested flycatcher being their 
most common enemies. 
20. Coleoptera. — The Coleoptera (co-le-op'ter-a : Greek 
coleos, shield; pteron, wing) are the beetles. The first pair 
of wings is horny and meets in a straight line down the back. 
The second pair of wings consists of thin membranes. The 
mouth parts are for biting. Among the harmful beetles are 
many wood borers, the May beetles, potato beetles, asparagus 
beetles, and weevils. Some 
of the beneficial beetles are 
the ladybug, which feeds 
on destructive and harm¬ 
ful insects, and the carrion 
beetle, that feeds on dead 
animals. 
The ladybugs are de¬ 
cidedly beneficial. Their 
larvse run over leaves and 
feed on other insects. 
Even as adults they con¬ 
tinue this good work. Hop 
growers appreciate the 
value of the ladybug larvae on their vines, as the ladybugs 
destroy the harmful hop lice. 
Through the investigations of the United States Depart¬ 
ment of Agriculture a certain kind of ladybug (Vedalia) was 
found in Australia, which is the natural enemy of an insect 
pest (cottony cushion scale) that was destroying the orange 
trees grown in California. This scale is a plant insect which 
was imported into the United States on young trees. Being 
freed from their natural enemies (Vedalia) which were not 
imported, they had increased rapidly. The prompt impor¬ 
tation of Vedalia put an end to the increase of the cottony 
cushion scale and they are now of no great economic impor¬ 
tance. 
Figure 18. — May Beetle. 
This is one of the commonest mem¬ 
bers of the Coleoptera. Note the an¬ 
terior wings which are shield-like and 
serve for protection. How do they 
differ from the second pair ? 
