Page 365. 
488 ON THE TRACHEA OF THE GALLINA. 
timate and penultimate rings, which is interrupted in front by the 
narrow cartilaginous isthmus between them. Above this the following 
twelve rings or so touch all round; and they are succeeded by typi- 
cally interlocking rings in the cervical portion of the tube. It must 
be also mentioned that whilst the plane of the penultimate tracheal 
ring is transverse, that of each lateral moiety of the last one, as 
well as the first bronchial semiring, runs upwards from its more fixed 
median anterior and posterior parts. The plane of the second semi- 
ring makes an angle of some 15° with the first. 
In this last respect, as well as others, the genus Pistia differs 
from Huplocamus. In Phasianus wallichii, P. colchicus, and P. versicolor 
the plane of each tracheal ring, as well as that of the uppermost 
bronchial semirings, is nearly, if not perfectly, transverse. The whole 
trachea. narrows slightly at its lower end, to expand again opposite 
the last two or three rings. As in Huplocamus, the last three rings 
fuse in the middle line behind, as do the last two (in P. wallichii the 
last three) in front, whilst in adult birds the anterior extremities of 
the first and second semirings participate in the blending, as does the 
pessulus posteriorly. In P. colchicus and P. versicolor (which differ 
from P. wallichii about as much as Euplocamus swinhoii does from its 
allies) there is a robustness about the last two tracheal rings and the 
first two bronchial semirings peculiar to them. Their direct front 
view always exhibits the posterior articulation of the first bronchial 
semiring with the ring above and the semiring below, as in no other 
Gallinaceous bird with which I am acquainted; thus, it includes the 
whole of the considerable interannular intervals between them, the 
Fig. 13. Fig. 14. 
Front view. Back view. 
Phasianus colchicus, 
