36 MISC. PUBLICATION 2738, U. S. DEPT. OF AGRICULTURE 
top and lower side. Species which attack the twigs of coniferous 
trees usually belong to the genera Anthaxia, Chrysophana, Chryso- 
bothris, or Melanophila. ‘There are many small species of flatheaded 
borers which mine under the bark and kill the twigs of broad- 
leaved trees. Some of the most striking work of this character is 
done by species of Agri/us, which make spiral girdles in the twigs 
FIGURE 16.—Spiral twig girdling is characteristic of Agrilus. 
of oak, birch, willow, and other broadleaved trees (fig. 16). Some 
of the western flatheaded twig borers and girdlers include the 
following: 
Species Hosts and distribution 
Anthagvia aeneogaster Cast______ Pines, firs, cypress, redwood, oak, willows, 
and other forest and shade trees. West- 
ern States. 
Chrysophana placida Lec__----_- Pines, firs, cedars, and hemlock. All West- 
ern States. 
Chrysobothris mali Horn (15)-— Alder, ash, aspen, beech, maple, poplar, 
willow, and many other’ hardwoods. 
Throughout the Western States. 
Chrysobothris femorata F. (15)__ Alder, ash, aspen, oak, poplar, willow, maple, 
beech, and many other hardwoods. 
Throughout the United States. 
Agrilus angélicus Morne 222 Oak. California. 
AGTIVULS: DOVITUS “Say. 2 ee ee Alder, willow, and other broadleaved trees 
and shrubs. 
AQrilus -anDiUs: GOry == 2s a: Birch, willow, and aspen. Eastern States 
and west into Colorado and Idaho. 
Agrilus bilineatus Web 22 222 Oak and chestnut. Eastern States and west 
into Colorado. 
The adult long-horned beetles of some species of the family 
Cerambycidae girdle the limbs and twigs of various hardwoods and 
thus prepare them for the feeding of the larvae. These roundheaded 
