The daily union. [volume] (Washington [D.C.]) 1845-1857, 1851-03-09
From the National Intclligsncer

Smithsonian Lectures.
The subject of Dr. Goadbys concluding lecture on
ment Of he Nks efon IaSecs" The lecturer stated that
IN this class Of aNmals and throughout The artenlsed
cub kingdom The hard paris OF True skeleton are ceyelop
ment gives protection 10 The internal organs, and forms
a basis for the attachment OF the muscles In chemical
composition il consists OF all the elements of horn 10
which is added albumen, the phosphaes of iron, lime,
and magnesa. with peculiar substance called chitne
aud colong matter is formed OF three Goals layers,
viz the tpldeyms. rele mueosum, and the csriunl.
An insect is divided into three distinct portionshead,
chest and body; and each OF these parts is subject TO
further division, the details of which we've demonstrated
and explained in disseced skeleton OF aquatic beetle,
the dyt,cas marginahs The first odhcauon OF struc
ture illustrated by the skeleton of tree bug hays
The skeleton OF the American cockroach form
ed the next Illustration The head dlsseced 10 show
the upper and under lip, upper and under paws WIN he
muscles, iongne. chin &c The chest dvsbie mo iuee
segmsnis or rings, was also dlsseced 10 show Tue oJo
motive members belonging 10 these parts tesperutey,
and the segmenls which belong TO The oody compiesu
The skeleton Corresponding parts were shomn ~ .ae
disseced skeleton of the maH regtOs4, or rear hoise
In all the foregoing skeletons the hfee ehei DIVISIONS
were represented be freely arculaed or loh'ea To-
geher and easily separable; but IN the skeleton oil IL
belua or dragon fly, beautiful modification was point
ed out The head is OF large SIZE WIN hemisphencal
compound eyes. OF such magnitude as 10 form agreat pro-
portion of The skull The upper Jaws are short, strong
and provided with very powerful muscles, particularly
those muscles whose office il is to close The mouth. The
first segment OF the chest carrying the first pair of legs
is small and may be easily separated from The head in front
and the second segment OF the chest behind The second
and third segnenls OF the ches! shown together and
in sections made in The direction OF the long axis OF the
body The lecturer pointed out the lines OF demarcation
which defined the limits OF the bones in appostion but
stated that they all sodereG or anchylos together
that they could not at all be separated The intention
of this arrangement concentration of strength in the
skeleton which is thus firmly knit together give
attachment to the very powerful muscles which nearly
fill these two large segmens OF the chest, and destn
ed to the of the wings Moreover, IT is necessary
that this part of the skeleton be nordnaely firm TO
able II TO endure the action OF these animals.
In its habits and mode OF life. the dragon y to the
insect world, what the hawk is among the bird Feeding
entirely upon insects, many Of them swift CT flight, the
dragon-hy may be skmming the surface of ponds,
necessarily on the wing in search OF It's prey The great
size and acute vision OF its compound eyes enable il to
discern an insect at distance when with the speed
OF lightning flash and unerring precision II strikes It's
quarry, sezing it with lis two pairs of jaws and hold
ing firmly by the under, whilst the upper jaws crush
and divide the creature, which is consumed
than this Unsuitable insect may be the
wing, searching lis domain for another victim. To tit II
for such life. has been gifted with the compac!ness
and solidy OF the bones OF It's skeleton just described
whilst the unusually large size OF the wings composed OF
gauze OF great strength but exquisite ghiness supported
by uneQuaed distribution Of the hollow wing bones
and put in motion by muscles Of considerable power
dows with capabilities Tor flight that are unsurpassed
and the elongated form OF its body is emnenty service
Notwithstanding that eight nights have been devoted
to the subject OF the Structure and Function OF Insects
aided by no less than twelve dozen of preparations many
of them OF great decay and all of them of surprising
beauty we are only now on the threshold OF this subject
vast that long life might be given to the study OF this
ono CLASS vi yet leave
plished. AS class insects have great claims upon ou
best attention. as they exert remarkable influence in the
scheme OF creation, and the injuries which result iron
species are fully compensated by the benefits confer
red by others. In proof of the latter assertion mus
not forget that
/. Insects maintain the balance between the ANNA
and vegetable Kingdoms.
2. They remove dead and decomposing animal ant
vegetable matter
3. They destroy noxious insects
4.'They as the food Of other animals, important
10 man.
They promote the fertilization of plants.
With regard to their immediate benefits, beetle pos
sesses the biserlng principle so important in medicine,
One species Of produces The cochinea used il
the arts and another the shellac, while the cynps OF thu
oak produces the gals of which writing ink made
The bee gives us wax and honey, while caterpillar doe.
80 much for us that probably present in the lee
ture room is less adorned with the nspissatet
savary secretion Of the skwormfor such the origin
of silk Finally, they all have their uses, and ma,
fairly quote the sentiment beautifully expressed BY
the late Rev. George Crabb:
Each shell, each crawling insect, holds rank
Important in the plan OF HIN who lramsd
This scale of beings-holds rank which lost
Would break the chain, and leave belIiGd gap
Which Natures self would rue"