1882. ] ANATOMY OF ERETHIZON DORSATUS. 277 
of the ceeeum which is opposite the entrance of the ileum. This band 
is much more marked on the colon of Hystrix cristata than on that 
of Erethizon. There is the normal ileo-czecal valve, aud besides 
this a very remarkable valvular constriction, or circular reduplica- 
tion (c), at the entrance into the large intestine from the cecum. 
It is something like the pyloric valve, only less defined, especially 
on one side’. An essentially similar structure exists in the Guinea- 
pig, of which I have not met with any description. There is 
no spiral valve in the cecum, but only a series of constrictions 
Abdominal aspect of the liver of Hrethizon dorsatus. 
Letters as before ; and C, caudate lobe; 4.a, hepatic artery ; 4.d, hepatic 
duct ; p.v, portal vein. 
corresponding to the sacculi formed by the longitudinal bands. 
There are no Peyer’s patches ; but there is a chain of glands (sixteen, 
single or in pairs) which extends across from the ileo-czecal valve to 
the czeco-colic aperture. 
The “iver consists of the normal four large lobes, with a small 
Spigelian and caudate lobe. There was, however, no gall-bladder 
in the specimen examined. Theright segment is much larger than 
‘ A preparation showing this structure, made from the specimen here 
described, has been preserved in the Museum of the Royal College of Surgeons. 
