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the third, the posterior lobe. The anterior margin of the pronotum is 
the margin next the head; the posterior margin is the hind margin of 
the dorsal portion, and is usually in the form of an angle, pointing 
backwards, or is rounded, but in a few species is truncated or cut off 
squarely; the posterior lateral margin is the hind margin of the later¬ 
al lobes. 
The prosternum is the underside of the prothorax or neck; it is 
either smooth, that is without a tubercle or spine, or it is furnished 
with a distinct tubercle or spine between the front legs, called the 
prosternal spine; the species furnished with this are said to have the 
prosternum spined , armed or mucronate; those without it are said to 
have the pro sternum smooth , or unarmed. 
The upper wings of Acrulidce are usually called elytra (which is 
the plural of elytron ), though by some authors they are termed hem- 
lytra , by others tegmina , and by others simply front wings. When 
the elytra and wings are spoken of together they are termed “wings.” 
The elytra are generally in the form of an elongate oval or an elon¬ 
gate parallelogram, narrowed at the base and rounded at the apex. 
In the perfect insect they usually reach to or extend beyond the tip 
of the abdomen; but there are numerous exceptions to this rule; in 
many species they are shorter than the abdomen, and in a few are 
wholly wanting. When the elytra are absent the wings are also want¬ 
ing. A little experience will enable any one to distinguish readily 
between a full-grown, short-winged insect of this family and one yet 
in the pupa state. When the elytra are folded' a small portion lies 
horizontally on the back, the remainder, and much the larger portion 
being deflexed vertically against the sides of the abdomen. When de¬ 
scribing them they are considered as closed; the upper edge, which 
runs along the back is termed the posterior , anal , or upper margin , 
some authors using one of these terms, some another; inner margin is 
also occasionally used for the same part; the lower edge is the costal, 
anterior or loiver margin; when “posterior” and “anterior” are used 
the elyra are then considered as spread. The area of each elytron is 
divided into three fields or spaces by two strong, longitudinal veins 
that start out from the base (part that joins the body); the larger of 
these, which runs a little distance from the costal margin, is the ex- 
terno-median vein or nerve; the other which runs from near the mid¬ 
dle of the base backward and upward toward the posterior or upper 
- margin is the interno-median vein. The three fields into which the 
area is divided by these veins have received the following names: that 
‘between the externo-median vein and costal margin, is the anterior , 
costal or lower field; that between the interno-median vein and the 
upper or posterior margin is the anal , posterior or upper field; the 
middle area lying between these two veins is the discoidal , biteryne- 
diate or middle field. The term area is often used instead of field, 
and is interchangeable therewith; the two words “vein” and “nerve” 
are likewise used interchangeably. The angle of the elytra is the 
longitudinal ridge formed along the interno-median vein by the sudden 
flexure from the horizontal to the vertical portion when closed. 
When describing the wings they are supposed to be fully spread. 
The terms disk and base are sometimes, though not correctly, used sy¬ 
nonymously, referring to the moiety of the wing next the body; the 
disk is really the central portion, and the base the part connecting 
with the body. The term submarginal , or subcostal area is used to 
