ON THE ANATOMY OF CHAUNA DERBIANA. 321 
The following table gives the intestinal lengths :-— 
é Q 
ft. in. ft. in. 
Small intestine...........++++- > ¢ 6 10 
Large intestine ..........++++: Lad 0 7 
SA as dawns « Saat habeas 0 3 0 2 
The duodenum, with its characteristic bend round the pancreas, is 
more capacious than the rest of the small intestine; but it is not 
large, being about + inch in diameter. The hepatic and pancreatic 
ducts enter it at the bend, 2} inches from the pylorus. 
The pair of ceca present a condition unlike that found in any 
other bird with which I am acquainted. In that they are situated 
some considerable distance from the cloaca, they agree only with 
Struthio and Rhea. In the mueh larger Cassowaries the large in- 
testine is not more than 7 inches long. In both Apteryz and the 
Tinamous, as well as in all other birds, the Anseres and Galline 
included, the large intestine does not exceed 4 inches in length. 
Chauna in having a large intestine, the length of which is several 
times the diameter of the gut, agrees therefore with Struthio and 
Rhea only. These organs are figured in Plate [15] XIII, they being 
opéned up in fig. 1 to show their internal structure. 
_ Instead of being smooth externally, the ceca are sacculated on 
two longitudinal bands. They are peculiarly capacious for their 
length, and fusiform in general outline. The sacculating bands are Page 192. 
not lateral, but on their outer and inner borders, being continued 
from the longitudinal fibres of the large and the small intestine. 
Their mucous membrane is uot plicated when they are distended. It 
is only, among other birds, in Struthio and Rhea that the ceca are 
sacculated ; in these, however, there is only a spiral twist like that in 
the cecum of the hares and rabbits. 
Each cecum has a well-developed special sphincter muscle guarding 
its aperture of communication with the intestine; and what is more 
peculiar still is, that they do not open into the colon proper, but into 
a special cavity, a continuation of the main intestinal tube, but 
separated off by a very constricting sphincter from the colon, as well 
as by the ileo-czecal valve from the small intestine. This ileo-colic 
cavity is = of an inch long and about } an inch in diameter when un- 
distended. Its mucous membrane is like that of the ceca, much more 
; delicate than that of the colon. The ileo-cecal valve is a small slit- 
like opening, nearly } of an inch long, with its lips projecting a little 
way into the ileo-colic cavity. The two openings of the ceca into the 
same cavity are one on each side of it, a little oblique in regard to it, 
and considerably larger in lumen. The opening into the colon is very 
constricted; beyond it the mucous membrane of the large intestine is, 
Y 
