[ 20 9 ] 
There is no occafion to defcribe here all thefc 
bags, or their attachments ; it being fufficient to fay, 
that they extend over the whole abdomen. 
The lungs open at their anterior part, that is, 
towards the fternum , into certain membranous cells 
which lie upon the Tides of the pericardium , and 
communicate with the cells of the Jlernum. 
The fuperior part of the lungs opens into the 
large cells of a loofe net-work, through which the 
trachea, oefophagus , and large vefiels, going from, 
and coming to the heart, pafs. 
When thefe cells are diftended with air, it en- 
creafes the fize of that part, where they lie, very 
confiderably j which, in general, is a mark of paf- 
fionj as appears evidently in the turkey-cock, the 
pouting-pidgeon, &c. and is extremely vifible, in 
the bread of a goofe, when fhe cackles. 
Thefe cells communicate with others in the 
axilla , under the large pectoral mufcle, &c : and 
thofe again with the cavity of the os humeri , by 
means of fmall openings, in the hollow furface, near 
the head of that bone. 
The pofterior edges of the lungs, which lie on the 
Tides of the fpine, and projedt backwards between 
the ribs, open into the cells of the bodies of the 
vertebra, thofe of the ribs, the canal of the me- 
dulla fpinalis , the cells of the facrum , and other 
bones of the pelvis ; from which parts the air finds 
a palTage to the cavity of the thigh-bone. 
This account agrees with what we find in mod 
birds ; though fome have more, and fotne fewer of 
thefe communications. 
E e 
Vol. LX IV. 
In 
