JO 
INSECrS. 
stance, viz. the stem seeming to pass through the 
leaves. This kind of Antenna is exemplified in 
some of the shell-winged or Beetle tribe. 
Another part peculiar to Insects consists in a 
]iair or two of short, jointed processes proceeding 
from the mouth : they are termed Palpi or Feelers, 
and are very conspicuous in some insects, and 
much less so in others. 
The Mouth in insects is generally situated at 
the lower part of the front, and varies much in 
structure in the different orders. In the Beetle 
tribe it is furnished with very strong jaws, often 
notched or serrated on the inner side into the ap- 
pearanee of teeth: this is also the case in Locusts 
and many other inseets. In some the mouth 
consists of a tube or instrument for suction, either 
simple, or variously sheathed and guarded by dif- 
ferent kinds of appendages. In such insects as have 
jaws, it is observable that they do not meet per- 
pendicularly, as in quadrupeds and birds, but 
horizontally. 
So great is the variety in the structure of the 
mouth in the different tribes of Insects, that a 
celebrated Entomologist (Fabricius,) has formed 
his System from this part in preference to any 
other. It must be observed however, that this 
mode of arranging insects is attended with much 
difficulty, and seems far inferior to the obvious 
and easy characters which distinguish the Linnasan 
distribution. 
The Eyes in Insects are commonly situated on 
each side the head, and are two in number i but 
