150 CRUSTACEA, ARACHNIUES, INSECTA. 
ably elongated, as are also the jaws, forming a sort of false proboscis 
(promuscis ) at the base of which is the pharynx, and frequently 
covered by a sort of sub-labrum, styled by M. Savigny the epipha- 
rynx * *. At other times, in the Hemiptera and Diptera, the mandibles 
and maxillcG are replaced by scaly pieces in the form of setee, which 
are received in an elongated tubular sheath, that is either cylindrical 
and articulated, or formed with more or less of an elbow, and termi- 
nated by a kind of lips. In this case they constitute a true proboscis. 
In others that also live by suction, the Lepidoptera, the maxillae, 
alone are greatly elongated and united, producing a tubular setiform 
body, resembling a long, slender, and spiral tongue (or the spiri- 
irompe, Lat.) ; the remaining parts of the mouth are considerably 
reduced. Sometimes again, as in many of the Crustacea, the anterior 
feet approach the maxillse, assume their form, and exercise part of 
their functions — the latter are then said to be multi])lied. It may 
even hai)pen that the true maxillee become so much reduced, that 
the maxillary feet supply their place in toto. AVhatever be the 
modifications of these parts, however, they can always be rccognizcrl 
and referred to a. general typef. 
properly so called ; notwithstanding this, nearly all Entomologists designate this 
external extremity of the lip hy the name of liyulu or lunyueltc. To say, however, 
that the tongue properly so called, is usually so intimately connected with the lip 
that at the first glance they seem to be confounded, is correct. The pharynx is situ- 
ated in the middle of the anterior face of this lip a little above it.s root, and in tlic 
Colcoptera provided with paragiossfc, at their point of union. In order to under- 
stand well the primitive composition of the under lip, it must be stiulied in the larvae, 
and chiefly in those of the Aquatic Carnivorous Cole(;ptera. See General Obser- 
vations on Insects. 
* There is a membranous production beneath the labrum, in many Colcoptera, 
which appears to me to be analogous to the epipharyux. The latrum is to it, what 
the mentum is to the labium. 
• "b It is only by a comparative and gradual study of the mouth of the Crustacea, 
that we can acquire correct and exact ideas respecting the various transformations 
of these parts, and the means of establishing, if not a certain, at least a probable 
general concordance between these various organs in the three classes. The man- 
dibles, maxilla;, and the labium, are in fact, a sort of feet appropriated to the masti- 
catory or buccal functions, but susceptible of being so modified as to become organs 
of locomotion. This principle even extends to the antenna;, or at least to the two 
intermediate ones of the Crustacea. By adopting it, we are enabled to reduce the 
composition of these organs to one general type, and we shall hereafter see that, in 
this respect, neither the Arachnides nor Myriapoda present any anomaly. 
