i4§ Mr. Thomas’s anatomical Description 
mesenteric vessels wereinjected, puton a beautiful villous appear- 
ance : it would appear, that they answer the same purposes as 
the valvulee conniventes in the human subject ; they differ only 
in the mode of arrangement, and are unlike what I have ever 
observed in any other animal. 
The liver was of a dark black colour, very soft, giving as 
little resistance to pressure as the human spleen generally does : 
it was divided into several lobes. The gall bladder was wanting. 
The spleen and pancreas were very similar to those of the 
ox. The kidnies were large, and considerably flattened : they 
were lobulated, but their lobes did not appear so distinct as 
those of the same gland belonging to the bear; probably, as 
the animal advances in life, this appearance may be altogether 
lost, as takes place in the human body, and a variety of other 
animals. Upon throwing some size, coloured with Vermillion, 
into the emulgent artery, I was surprised to perceive the co- 
loured matter escape by the ureter, without any considerable 
pressure of the piston : this circumstance induced me to insert 
the pipe into the excretory duct of the other kidney ; when the 
injection escaped, with the same ease, by both artery and vein. 
I should not have noticed these circumstances, which have oc- 
casionally occurred to me when injecting the human kidneys, 
and also those of other animals ; but, in these instances, the 
great facility with which the injection passed, surprised me, and 
at the same time proved, in a remarkable manner, the simple 
structure of this gland. The organs of generation had not ar- 
rived to maturity : the testes were small, and situated without 
the abdomen ; the vasa deferentia did not allow quicksilver to 
pass along them ; and, upon the whole, it was evident the testes 
never had secreted. The vesiculae seminales were cellular 5 
