92 
COLEOPTERA. 
resemble in form the grubs of some of tbe small Scara- 
bajians. 
The shagbark or walnut tree is sometimes infested by tbe 
grubs of tbe red-shouldered Apate, or Apate basillaris of 
Say, an insect of this family. The grubs bore diametrically 
through the trunks of the walnut to the very heart, and 
undergo their transformations in the bottom of their bur- 
rows. Several trees have fallen under my observation which 
have been entirely killed by these insects. The beetles are 
of a deep black color, and are punctured all over. The 
thorax is very convex and rough before ; the wing-covers 
are not excavated at the tip, but they slope downwards very 
suddenly behind, as if obliquely cut off, the outer edge of 
the cut portion is armed with three little teeth on each wing- 
cover, and on the base or shoulders there is a large red spot. 
This insect measures one fifth of an inch or more in length. 
The most powerful and destructive of the wood-eating 
insects are the grubs of the long-horned or Capricorn-beetles 
(Cerambycidjs), called borers by way of distinction. There 
are many kinds of borers which do not belong to this tribe. 
Some of them have already been described, and others will 
be mentioned under the orders to which they belong. Those 
now under consideration differ much from each other in their 
habits. Some live altogether in the trunks of trees, others 
in the limbs ; some devour the wood, others the pith ; some 
are found only in shrubs, some in the stems of herbaceous 
plants, and others are confined to roots. Certain kinds are 
limited to plants of one species, others live indiscriminately 
upon several plants of one natural family ; but the same 
kind of borer is not known to inhabit plants differing essen- 
tially from each other in their natural characters. As might 
be expected from these circumstances, the beetles produced 
fi'om these borers are of many different kinds. Nearly one 
hundred species have been found in Massachusetts, and 
probably many more remain to be discovered. 
The Capricorn-beetles agree in the following respects. 
