LA II 
case a hardness greater than that of the 
wood itself in its natni al slate. Tliis is the 
strange horned caterpillar of the willow, 
which is one of those that eat their exuviae. 
This creature has extremely sharp teeth, 
and with these it cuts the wood into a num- 
ber of small fragments ; these fragments it 
afterwards unites together into a case, of 
what shape it pleases, by means of a pecu- 
liar silk, which is no other than a tough and 
viscous juice, which hardens as it dries, and 
is a strong and firm cement. The solidity 
of the case being thus provided for, we are 
to consider, that the caterpillar inclosed in 
it is to become a butterfly; and the wonder 
is, in what manner a creature of this help- 
less kind, which has neither legs to dig, nor 
teeth to gnaw with, is to make its way out 
of so firm and strong a lodgment as this in 
which it is hatched. The butterfly, as soon 
as hatched, discharges a liquor which sof- 
tens the viscous matter that holds the case 
together ; and so its several fragments firll- 
ing to pieces, the way outlies open. Reau- 
mur judged, from the effects, that this 
liquor must be of a singular nature, and 
very different from the generality of animal 
fluids ; and in dissecting this creature in the 
eaterpillar state, there will always be found 
near the month, and under jhe oe-sophagus, 
a bladder of the size of a small pea, full of a 
limpid liquor, of a very quick and pene- 
trating smell, and which, upon trial, proves 
to be a very powerful acid; and among 
other properties, which it has in common 
with other acids, it sensibly softens the glue 
of the case, on a common application.- It 
is evident that this liquor, besides its use to 
the caterpillar, remains with it in the chry- 
salis state, and is what gives it a power of 
dissolving tlie structure of the case, and 
making its way through in a proper manner 
at the necessary time. 
Boerhaave adopted the opinion that there 
are no true acids in animals, excejit in the 
stomach or intc.stines ; but this familiar in- 
stance proves the contrary. Another very 
curious and mysterious artifice is that by 
whicli some species of caterpillars, when the 
time of their changing into the chrysalis state 
is coming on, make themselves lodgments in 
the leaves of the trees, by rolling them up 
in such a manner as to make themselves a 
sort of hollow cylindric case, proportioned 
to the thickness of their body, well defend- 
ed against the injuries of the air, and care- 
fully secured for their state of tranquillity. 
Jiesides tliese caterpillars, which in this 
LAR 
manner roll up the leaves of plants, there 
are other species which only bend them 
once, and others, which by means of thin 
threads, connect many leaves together to 
make them a case. All this is a very sur- 
prising work, but much inferior to this 
method of rolling. 
The different species of caterpillars have 
different inclination.s, not only in their spin- 
ning and their choice of food, but even in 
their manners and behaviour one to another. 
Some never part company from the time of 
their being hatched to their last change, 
but live and feed together, and undergo to- 
gether their change into the chrysalis state. 
Others separate one from another as soon 
as able to crawl about, and each seeks its 
lortnne single ; and there are others which 
regularly live to a certain time of their lives 
in community, and then separate, each to 
sliift tor itself, and never to meet again in 
that state. See Entomology, Insects, &c. 
LARUS, the gull, in natural history, a 
genus of birds of the order Anseres. Ge- 
neric cliaracter : bill strong, straight, siiarp 
edged, bending down somewhat at the tip ; 
lower mandible e.xhibiting an angular pro- 
minence ; nostrils in the middle of the bill, 
body light ; wings long; legs small, and 
naked above the knee ; back toe small. 
They inhabit principally the northern cli- 
mates, subsisting on carrion, and on fishes. 
They are reported, when greatly alarmed, 
almost universally to throw up from their 
stomach the food they have recently swal- 
lowed. Gmelin reckons fifteen species, 
and Latham nineteen. L. marinus, is 
twenty-nine inches in length, and of the 
weight of five pounds. It is found in va- 
rious parts of England, and on most of the 
iiortliern coasts of Europe. It breeds in the 
most elevated cliffs, laying its eggs on heaps 
of dung deposited by various birds. It 
teeds principally on fishes, but sometimes 
attacks birds, and i,s said to hear a particu- 
lar enmity to the eider-duck. See Aves, 
Plate IX. tig. 2. 
L. fiiscus, or the herring gull, is some- 
what less than the former, frequents the 
same situations, and subsists, like that, 
chiefly upon fish. In the herring season it 
is seen watching the nets of the fishermen, 
and is daring enough frequently to seize its 
prey from tlie boats and nets. 
L. canus, or the common gull, is sixteen 
inches long, and about a pound in weight. 
It breeds on the rocks and cliffs on the Bri- 
tish coasts, and on the banks of the Thames, 
