542 
L. H. FRIEDBURG. 
peculiar distinctness in the dog. The fold is not correctly- 
shaded and should extend on the meso-colon descendens from 
18 to 24, i.e., the insertion of the fold marked at 25, is at con¬ 
siderable distance from the root of the meso-colon descendens. 
This fold is, in my opinion, due to the rotation of the navel 
loop. The caecum started at 12 and travelled, by the aid of 
growth and rotation of the navel loop, to the adult home in 
the right iliac fossa. Developmental processes in the peri¬ 
toneum may be easily observed in the various species of 
animals. 
Fig. 2 is a life-sized drawing which I sketched from a 
gray tree-squirrel (rodentia) to represent the caecum and first 
or lower loop of the ascending colon. It is drawn as closely 
as possible to nature in size and form. 1, 9 and 4 mark the 
artery which supplies the bowels. 8 and 7 mark the lower 
loop of the ascending colon. 2 marks the ascending colon , 
between the lower and the entering ilium. 3 notes the artery 
passing behind the ilium. 5 and 6 mark the caecum. Its 
exact proportions are represented to the ascending colon 
from a squirrel with a body twelve inches long. The mon¬ 
strous caecum fills almost the entire lower (posterior) abdomen. 
The danger of such a caecum is volvulus. In the squirrel it 
lies more in the left cavity than in the right. It is much less 
in size in proportion to the rabbit. The squirrel has no ap¬ 
pendix except what is seen in the picture. The peritoneal 
folds of the squirrel are much more extensive and liberal than 
in man. No peritoneal adhesions of any kind were found in j 
this squirrel. The caeca of the herbivora, rodentia and soli- j 
peds which I have carefully examined, as to size, relations 
and peritoneal coverings, seem to be the remnant of some 
ancient stomach, or pouch where food could tarry until it 
was absorbed or utilized. ) 
ON IRON AND ITS ASSIMILATION BY THE ORGANISM. 
By L. H. Friedburg, Ph.D., Professor of Chemistry and Toxicology, American 
Veterinary College. 
____________ 
In a paper read before the Academy of Medicine, on 
Tuesday, October 15, 1895, I took occasion to state mainly 
the following points in regard to the above question: 
