The minimum equipment necessary to collect insects consists

THE PROJECTION OF LIVING INSECTS
insecr. in a watch gla.s cec be projccled lor smal) groups with. a
phoLographic enlarlcr or 'imilai projcctor. or lhe inscLls can bc
iri l"-ro'u ,;zid ruarcr cell ard projecred lot larger, group'
i4'ith a .[L]e
"lide proieclor 't]e more practicdl melhod l ne con-
.truction of sucb-a rvater cell is illusrrated belorv'
1,j,, F.__-*",ghl
-:7-;i:::- 2x? 5t1de
l-t-'fft fil
I I
llll,llllll
H lil lllll
i l ltl tu]
,--= lu_ll
A vater cell for projecting small living aquatic animals'
The Structure of Insects
A (NowLEDcE oI inscct structure is essentiai to understanding
de,criptions arJ th, , harrclers ,li.rirrBui-lring diffcrcnl groul".
The following account is rather brief; more information is given
in l\c ar court: of .orre uf lh. insp, r orde s.
General Structure. The bodl' of an insect is segmentcd and
more or lcss elolgated. Thc rcgments are g.ouped in 3 body
regions, the head, thorax, and abdonen. 'l'he redd bears thc cyes,
antennae, and mouth parts; the ,rrl.ri bears the lcgs and tvings;
the abd.otuen usr.rally bcars no locomotor appendagcs but olten has
some appendages at its posterior end.
An insect's body r,r.all is somenhat hardencd. (sclerotized.). It
serves as a shell to protect the intemal organs and acts as a skclcton
or, more properly, eroskeleton (muscles are attached to ils inner
surface). The surlace of the body is divided by intersegrnental
and other lines into a number oI piatelikc arcas, or sderitei.
The Head. The head is the antcrior capsulelikc body region
that bears thc cyes, antennae, and rnouth parts. It is usually quite
hard. The surfice-is divided by sutures into a number oi a.ieas,
each with a name; the samc names are used irt diflerent insect
groups where the areas can be homologized but special terms
are used in some groups.
Insects generaliy have 2 kinds of eyes, simple and compound.
For the majority there are 3 simplc eyes (orelli), located on the
ypper lronl parl o[ lhe hea,l. Some jnscr ts laek ocnlli and others
have only 2- 'lhe , ompou'd ey", are .:tuated dur.olarL rally on trrc
bead, each composed ol mdry ir.er-. I. in.ect- they occupy
most of the head and contain hundreds of
"olre
lacets.
The Antenrae are usuallv located on the front oI the head below
the ocellil thpy vary er, ar li in forn and :n lhe numbcr uf -egmeclconlained,
and are often u-ed to di.tirrgui"h diFlerent:n.ecl proups.
Various terms that describe the antinnae are explained ln the
accounts of thc ArouDs in which .rntennal chdracters are u5ed lor
identification-
_ Mouth Parts. The mouth parts of an insect generally are
located on lhe rentral or ante"ior part ot thc hrad, und rh, 1'ur.y
a greal deal in diflerent ins"ct group.. T\c mout\ pa-1 .rru,-ture!
typically pre-ent are a labum,uop.r lip), a pair ol ja\\ like , ?rklibks,
a pair ot jawlike naxilLae, a l.rLium tlo\\er lipl, and a longuelrke
structure called the htboDh,Jt \)nr:.
- Insecl moulh parts ar" of ) g"neral tlpes, cheuirg ard sucling.
Insects with cheuing mourh pins hare laterally morirg mardi-
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