so 
LACEET A, 
was lengthened after it became fafliionable, which was not 
till the civil wars and the triumvirate; before this time it 
was confined to the foldiers. Senators were forbidden 
wearing it in the city by Valentinian and Theodofius. 
Martial makes mention of lacernae worth 10,000 felterces. 
Some confound this garment with the penula ; but it 
feems rather to have refembled the chlamys and birrus. 
LACER'TA, f. [from laeero , to tear, on account of the 
voracity of the larger fpecies ; or from lacertofus, brawny, 
finewy, ftrong.] In zoology, a genus of the clafs amphibia, 
order reptilia; including the crocodiles, lizards, water- 
newts, chameleon, falainander, &c. Generic charafters : 
Body four-footed, elongated, tailed ; naked, i. e. without 
any fecondary integument. 
This is the molt numerous genus in the tribe of ovipa¬ 
rous quadrupeds. The animals of this genus are eafily 
diltinguilhed from all other oviparous quadrupeds, as 
they have no bucklers, like the tortoifes 5 and are all 
furnilhed with tails, which are entirely wanting in frogs 
and toads. Their bodies are covered either with fcales 
of more or lefs ftrength, or with tubercles of greater or 
lefs projection. Their length varies, in the different 
fpecies, from two or three inches, to twenty-fix or 
even thirty feet. Their tails differ both in general form, 
and in proportion to the fize of the body; being flat in 
fome fpecies, and rounded in others; in fome fpecies three 
times as long as the body, in others very fhort; in all the 
fpecies the tail is extended horizontally backwards, and 
is almoft as thick at the bafe as the hinder part of the 
body from which it arifes. In general the hind legs are 
longer than the fore, though Linnaeus makes pedibus equalibus 
part of the generic chara&er. Some fpecies have five toes 
<on each foot, while others have only four or three on the 
fore feet, or only on the hind feet. In moll of the fpecies, 
the five toes of the hind feet are of unequal lengths; the 
third and fourth being longer than the reft, and the outer 
toe is feparated from the others, fo as to form a kind of 
thumb, while, in all the viviparous quadrupeds, the toe 
which ferves this purpofe is the inmolt. The phalanges, 
or moveable pieces, of the toes, in this genus, are not con¬ 
fined to three for the fingers and two for the thumbs, as 
in viviparous quadrupeds, but fometimes extend to four, 
as in fome fpecies of birds, which gives greater facility for 
grafping the branches of trees in climbing. 
The different fpecies of this genus differ from each other 
in habits, as much as in external form. Some live almoft 
entirely in the water, or on the fequeftered banks of great 
rivers and marfhes. Some, inftead of avoiding the habi¬ 
tations of mankind, feem to prefer thefe to all other places. 
Some live in the woods, and run with great fwiftnefs along 
even the higheft and moft {lender branches of trees. 
Moft of the lizard tribe have only two or four vertebras 
of the neck ; but the crocodile, which, from its power and 
fize, ftands at the head of all thefe animals, has feven, like 
all viviparous quadrupeds. Thus that fpecies may be con- 
fidered as conne&ing the lizards with the fuperior orders 
of viviparous quadrupeds, while, by its habits and ftruc- 
ture, it connects them with the tortoifes. The falaman- 
der, on the contrary, feems to unite the genus with a 
lower order of oviparous quadrupeds, and thus aftifts to 
form and fupportthe wondrous chain of animated nature. 
As this genus includes fo great a number of fpecies, it 
was thought neceflary to reduce them into fome metho¬ 
dical arrangement, uniting together fuch as refernble eacji 
other in fize, external form, and general habits. For this 
purpofe, the genus is here arranged into eleven divifions. 
But fuch divifions neither are, nor can be, perfeftly pre- 
cife ; fince fpecies may occur which may with almoft equal 
■propriety be referred to either of the neighbouring fec- 
t.ons; but in general they will be found ufeful in the in- 
vefligation of the fpecies. 
I, Tail two-edged, and divided into fegments ; tongue very 
Jhort ; five toes on the fore feet, four on the hind feet. 
i, Lacerta crocodilus, the common or Nilotic crocodile. 
Specific charafter, head mailed, neck earinated, and twtf 
lateral crefted procefies on the upper part of the tail. 
The crocodile, in its general form, is extremely fimilar 
to the other lizards, but has a number of diftinftive cha¬ 
racters peculiar to itfelf. The head is long, flattened, and 
much wrinkled ; the muzzle being thick, and fomewhat 
rounded. On the upper part of the muzzle, there is a 
round, blackiftr, foft, fpongy, fubftance, in which the nof- 
trils are placed ; which are of a crefcent figure, having the 
points turned backwards. The mouth is enormoufly 
large, opening even behind the ears, the jaws being fome¬ 
times feveral feet in length : the lower jaw is perfectly 
ftraight on both fides ; but the upper jaw is waved in its 
direction, and is much enlarged at its pofterior extremity, 
fo as to overlap the under jaw on each fide; it becomes 
narrower at the fides, and is in its turn overlapped by the 
under jaw, almoft to the muzzle, where it again enlarges, 
and overlaps the under jaw. From this circumitance, the 
teeth that are fituated at thefe overlapping places, have 
the appearance of tufks or canine teeth ; fuch as the ten 
teeth in the front part of the upper jaw. On the other 
hand, the two foremoft teeth of the lower jaw, when the 
mouth is (hut, not only penetrate into the upper jaw, but 
even proceed quite through it, and appear on the outfide 
like two fmall horns. This circumftance is very evident 
in all the individuals of any confiderable fize ; and is even 
perceptible In a young fpecimen from Senegal, only four 
feet four inches long, preferved in the royal cabinet at 
Paris. Notwithftanding the diftinClnefs of this remark¬ 
able character, Cepede fays it has not been hitherto no¬ 
ticed by any naturalift, except by the Jefuit mathemati¬ 
cians who were fent into the eaft by Louis XIV. and wlu> 
fent home the defeription of a crocodile from Siam. 
There are fometimes as far as thirty-fix teeth in the up¬ 
per jaw, and thirty in the lower ; but the number is fub- 
jeCt to variety. The teeth are of different lengths, very 
ftrong, fomewhat hollowed, ftriated on their lateral fur- 
faces, of a conical form, and fharp-pointed ; they are firm¬ 
ly fixed in the jaws, by means of ftrong roots, forming a 
Angle row on each fide of each jaw, and are fomewhat bent 
or hooked backwards, efpecially thofe neareft the muzzle. 
They are fo fituated in the two jaws, relatively to each 
other, that they pafs between each other when the mouth 
is fhut; and, in this fituation, the points of feveral of the 
lower teeth are received into the hollows in the upper 
gums, and of feveral of the upper teeth into fimilar hol¬ 
lows in the gums of the lower jaw. The gentlemen of 
the academy, who difleCted a very young crocodile in 
1681, having drawn out feveral of its teeth, found others 
of a very fmall fize in the bottoms of the fockets; hence 
it appears, that the firft fet of teeth muft fall out, and be 
replaced by a new fet, in the fame manner with the inci- 
five teeth of mankind, and of many viviparous quadru¬ 
peds. 
Notwithftanding that feveral authors have infilled, that 
the upper jaw in crocodiles is moveable, it only needs a 
Angle glance at the fkeleton to be convinced that, as in 
all quadrupeds, the upper jaw is entirely fixed, and the 
motion is confined to the under jaw. In moft viviparous 
quadrupeds, befides the direCt vertical motion of opening 
and fhutting the mouth, the lower jaw has a lateral mo¬ 
tion from fide to fide, for the purpofe of grinding or chew¬ 
ing the food. This motion is denied to the crocodile ; 
which is only very imperfectly able to mafticate its food, 
becaufe the teeth are fo placed as not to meet, or oppofe 
each other ; but they are excellently calculated for keep¬ 
ing a fall hold of their prey, and for tearing it to pieces 3 
after which it is moftly fwallowed without chewing, and 
without being mixed with faliva : it is, however, very 
readily digefted, in confequence of the crocodile having a 
larger proportion of bile and gaftric juice than any other 
animal. In thefe refpefts, the crocodile has confiderable 
refemblance to the clafs of fifties ; and the teeth, in feveral 
fpecies of fharks, refernble thofe of the crocodile, both in 
figure and arrangement. 
3 The 
