THE ALIMENTARY TRACT 211 
Marsupials give such a high relative incidence that 
especial search of their records was made, mthout, how- 
ever, very definite result. In three of the seven cases an 
acute general infection existed, in one an acute peritonitis 
which seemed to emanate from a small ulcer in the ileum, 
in one an injury to the anal region was found while in the 
remaining two the notes would suggest that the lower 
intestine was atonic, judging by its distention, trans- 
lucency and pallor. In five the stoppage took place 
in the large bowel alone, in the others both divisions 
being affected. 
It is often difficult to establish a diagnosis of consti- 
pation in birds because many varieties form a long rather 
dry mass in the lower small intestine, to be moistened in 
the cloaca for discharge. Still again the groups with 
capacious ceca are apt to have them filled normally with 
firm casts. Diagnoses of fecal inspissation and stoppage 
in the smaller tube have been made seldom, but one must 
consider also the obstruction offered by excessive urate 
collections either in the cloaca or lower ileum which will 
amount to a constipation if the cloaca be over-dilated 
and dried urates mixed with dirt or feathers cover the 
anal opening. 
The causes of this condition in birds are usually 
mechanical, inflammation being found in a small minority 
of cases. In the small passerine birds, seeds, sand, or 
parasites form the commonest findings. This is also true 
of parrots, while excessive urate collections are noted for 
both these groups. The gallinaceous birds present two 
reasons for fecal stoppage — disease of the ceca (see 
pages 205-6) and cloacitis probably secondary to anal 
closure by excessive urate collection. Uratic stones, 
varying from one to five millimetres in diameter, have 
been found in the cloaca in several orders. In only one 
case, a pheasant, did they cause ulceration and cloacitis. 
Sand, rust, grains and the like are found frequently, and 
sometimes in groups of birds, indicating that the speci- 
