The aphides and all their brethren have a mouth differently constructed, being a long and slender pointed canal, of a fleshy, or leathery substance, but furnished internally with several slender bristles, which the insect employs as lancets to wound its prey. In the flea, again, the structure is quite different." [Illustration: _Proboscis of the Honey-Bee._] [Illustration: _Proboscis of Carpenter-Bee_] To the variations in the mouth of each of these insects it has been thought good to attach a distinct name. When, for example, we speak of a bee's _proboscis_,[V] we speak actually of its mouth. The mouth of the butterfly is called by most entomologists _antlia_; that of the aphis a _promuscis_; that of the flea a _rostrulum_. But the reader must not allow himself to be confused by these terms; they all are but names for modifications of the same part--the mouth. When the butterfly plunges its long tube into the flower--when the fly intoxicates itself with a drop of syrup, using its _proboscis_ to pump it up--and when the flea thrusts its _rostrulum_ into our flesh, and quaffs our life-blood as though it were nectar,--let us not forget the mouth is the organ employed in each of these cases, varied and altered in form though it certainly be. [Illustration: Diagram of the mouth.--_a._ The _Labrum_, or upper lip; _b._ The _Mandibles_, or upper jaws _c._ The _Maxillæ_, or lower jaws; _d._ The _Labium_, or lower lip.] In all cases, the various parts of the mouth may be reduced to six, the names of which deserve remembering, and this will be rendered easier by the accompanying diagram, in which they are all separated and lettered, so as to distinguish each part; these six parts consist of four side-pieces, and two other organs, one above, the other below. The name of the upper organ is the _upper lip_, or in Latin, _labrum_; that of the opposite lower one, is the _lower lip_, or _labium_. The upper pair, of side-pieces, are called the _mandibles_, or upper jaws; the pair below are the lower jaws, or _maxillæ_. Let us now briefly mention the use of these various parts of the insect's mouth; beginning with the upper lip, (_a_) or _labrum_. Unlike that organ in ourselves, the insect's upper lip is generally, in such insects as bite their food, a plate of horny substance, which serves the purpose of an upper covering to the rest of the mouth. Like our own upper lips, however, that is to say, like those of men, at least, it is fringed with a sort of _moustache_ in most cases.