C6z A N A T 
folved in our ftomachs by the adlion of a menftruum. But 
this metb.od of reafoiling is very faulty ; nor can it ever 
bring us to the true folution of any phiiofophical or medi¬ 
cal problem. It is very plain, fince the firufture of the 
parts of the human ftomach are fo very different from that 
of.tills creature, that it is foolifh and unreafonable to ima¬ 
gine both of them capable of producing the fame effects. 
At each end of the ftomach, there are as it were two par¬ 
ticular facs of a different texture from the reft of the fto- 
mach, not confiding of ftrong mufcular fibres; they feem 
to be receptacles for the (tones, (efpecially at the end which 
is fanned from the orifice,) while the digefted aliment is 
protruded into the inteftines. 
The duodenum begins near the fame place at which the 
cefbphagus enters; yet notwithftanding the vicinity of thefe 
two tubes, the aliments are in no dange-r of getting out 
before they are perfectly digefted, by reafon of a protube¬ 
rance, or feptum medium, between the orifices; and in thofe 
creatures who have fuch a ftrong mufcular ftomach, it is 
a matter of great indifference whether the entry of the 
oefophagus or pylorus be higheft, provided that the entry 
from the oefophagus does not allow' the food to regurgi¬ 
tate, fince the force of the ftomach can eaftly protrude it 
towards the duodenum. This gut is moftly in the right 
fide, and hangs pendulous in their abdomen, having its 
tw o extremities fixed to the liver. The duElus choledochus 
enters near its termination, where it mounts up again to 
be fixed to the liver; and left, by the contraction of the 
inteftines, the bile (hould pafs over without being inti¬ 
mately blended with the chyle, that duCt enters down¬ 
wards, contrary to the courfe of the food, and contrary to 
•what is obferved in any of the animals we have yet men¬ 
tioned. But (till the general intention is kept in view, in 
allow ing thefe juices the faireft chance of being intimately 
blended with the food. 
The fmall guts are proportionally longer than thofe of 
carnivorous birds, for the general caufe already affigned. 
At the end of the ilium they have two large intejlina cceca, 
one on each fide, four or five inches long, coming off from 
the fide of the reCtum, and afeending ; and we find them 
containing part of the food : thefe ferve as refervoirs to 
the fasces ; which, after fome remora, there regurgitate 
into what foon becomes the redtum ; which, together with 
the excretories of urine and organs of generation, empties 
itfelf into the common cloaca. The fmall inteftines are 
connedled by a long loofe mefentery, which has little or 
no fat accompanying the blood-veffels, there being no ha¬ 
zard of the blood’s being flopped. The pancreas in the 
cock lies between the two folds of the duodenum, and 
fends two or three dudts into this gut near the biliary duff. 
Their fpken is of a round globular figure, fituated between 
the liver and ftomach ; and between thefe and the back¬ 
bone it enjoys the fame properties as in other animals, viz. 
large blood-veffels, &c. All its blood is fent into the vena 
fortarum, and has a perpetual conquaffation. It has no 
excretory, as far as we know. Their liver is divided into 
two equal lobes by a pellucid membrane, running accord¬ 
ing to the length of their body. The fhape of their gall¬ 
bladder is not much different from that of quadrupeds ; 
but it is thought to be longer in proportion to the fize of 
the animal, and is farther removed from the liver. The 
principal difference to be remarked in the heart, is the want 
of the valvulce tricuj'pides, and their place being fupplied by 
pne fieftiy flap. 1 he lungs are not loofe within the cavity 
of the thorax, but fixed to the bone all the way; neither 
are they divided into lobes, as in thofe animals that have 
a large motion in their fpine. They are two red fpongy 
bodies, covered with a membrane that is pervious, and 
which communicates with the large vehicles or air bags 
that are difperfed over their whole abdomen ; which ve¬ 
hicles ferve two very confiderable ufes. The one is to ren¬ 
der their bodies fpecifically light, when they have a mind 
to afeend and buoy themfelves up when flying, by diftend- 
iag their lungs with air, and alfo firaiten their trachea ar- 
teiiay and fo retain the ait. Secondly, they fupuly the 
O M Y. [Comparative. 
place of a mufcular diaphragm and ftrong abdominal muf- 
cles ; producing the fame effedts on the feveral contained 
vifeera as the mufcles would have done, without the in¬ 
convenience of their additional weight; and conducing as 
much to the exclufion of the egg and fasces. 
When we examine the upper end of the trachea, we oh- 
ferve a rima gloltidis with mufcular Tides, which may a 61 
in preventing the food or drink from pafling into the lungs; 
for there is no epiglottis, as in man and quadrupeds. The 
trachea arteria, near where it divides, is very much con- 
tra6Ied; and their voice is principally owing to this coarc¬ 
tation. If you liften attentively to a cock crowing, you 
will be fenfible that the noife does not proceed from the 
throat, but deeper; nay, this very pipe, when taken out 
of the body, and cut off a little after its divifion, and blown 
into, wfill make a fqueaking noife, lomething like the voice 
of thefe creatures. On each fide, a little higher than this 
contradlion, there is a muicle arifing from their fternum, 
which dilates the trachea. The cartilages, of which the 
pipe is compofed in this animal, go quite round it; w here¬ 
as'in men and quadrupeds they are difeontinued for about 
one-fourth on the back-part, and the intermediate fpace is 
filled up by a membrane. In place of a mufcular diaphragm, 
this creature has nothing but a thin membrane connected 
to the pericardium, which (eparates the thorax and abdo¬ 
men. But befides this, the whole abdomen and thorax are 
divided by a longitudinal membrane or mediajlinum connec¬ 
ted to the lungs, pericardium, liver, llomach, and to the 
fat lying over the ftomach and guts, which is analogous to 
an omentum, and fupplies its place. 
The lymphatic fyfem In birds confifts, as in man, of lac¬ 
teal and lymphatic vcffels, with the thoracic dudi. The 
ladleals indeed, in the ftridteft fenfe, are the lymphatics of 
the inteftines; and, like the other lymphatics, carry only 
a tranfparent lymph ; and, inftead of one thoracic dudt, 
there are two, which go to the jugular veins. In thefe 
circumftances, it would feem that birds differ from the 
human fubjedt, fo far at lead as we may judge from the 
diffedtion of a goofe, the common fubjedt of this inquiry, 
and from which the following defeription is taken. The 
ladleals run from the inteftines upon the mefenteric veffels: 
thofe of the duodenum pafs by the fide of the pancreas; 
afterwards they get up the casliac artery, of which the fu- 
perior mefenteric is a branch. Here they are joined by 
the lymphatics of the liver, and then they form a pleius 
which furrounds the caeliac artery. Here alfo they receive 
a lymphatic from the gizzard, and foon after another from 
the lower part of the oefophagus. At the root of the cneliac 
artery they are joined by the lymphatics from the glan- 
dulae renales, and near the fame part by the ladleals from 
the other fmall inteftines, which veffels accompany the 
lower mefenteric artery; but, before they join thofe from 
the duodenum, they receive from the redluin a lymphatic, 
which runs from the blood-veffels of that gut. Into this 
lymphatic fome fmall veffels from the kidneys feein to 
enter at the root of the caeliac artery. The lymphatics of 
the lower extremities probably join thofe from the intef¬ 
tines. At the root of the creliac artery and contiguous 
part of the aorta, a net-work is formed by the veffels 
above deferibed. From this net-work arile two thoracic 
dudls, of which one lies on each (ide of the fpine, and 
runs obliquely over the lungs to the jugular vein, into the 
inlide of which it terminates, nearly opppfite to the angle 
formed by the jugular and fubclavian vein. The thoracic 
dudt of the left fide is joined by a large lymphatic, which 
runs upon the oefophagus. The thoracic duels are joined 
by the lymphatics of the neck, and probably by thofe of 
the wings, where they open into the jugular veins. The 
lymphatics of the neck generally confift of two large 
branches on each fide of the neck, accompanying the 
blood-veffels ; and thefe two branches join near the lower 
part of the neck, and form a trunk which runs clofe to 
the jugular vein, and opens into a lymphatic gland ; from 
the oppolite fide of this gland a lymphatic comes out, 
which ends in the jugular vein. On the left fide, the 
3 whole 
