30 BULLETIN 800, U. S. DEPARTMENT OF AGRICULTURE. 
interlobular connective tissue and the medullary portion of the 
lobules being more hemorrhagic than congested. The blood in these 
areas obscures the tissues of the gland. The thymus tissues of the 
steer are not congested, but have been invaded by numerous eosino- 
phile leucocytes. 
NERVOUS SYSTEM. 
The following portions of the central nervous system have been 
studied — cerebral cortex, cerebellum, hippocampus, medulla, and cer- 
vical and lumbar cords. In all parts there is a fullness of the capilla- 
ries which in some cases, especially in the spinal cord, is congestion 
rather than fullness. The varying condition found is simply one of 
degree. The most marked pathological condition found is in the 
cervical spinal cord of Sheep 492. In these sections there is pro- 
nounced capillary congestion, especially of the gray matter, with 
areas where hemorrhages have occurred. The perivascular and peri- 
cellular lymph spaces are much distended, as is the central canal. 
This condition exists in most of the sections of the central nervous 
system examined which included tissues from 4 sheep and 1 guinea 
Pig- 
LIVER. 
The only change characteristic of Asclepias poisoning noted in the 
liver is a slight though well-marked cloudy swelling of the hepatic 
cells. 
ALIMENTARY CANAL. 
In the abomasum and intestines of the sheep and the steer the 
changes as a rule are not severe. They are largely vascular and in 
most cases vary from fullness to mild congestion. Here the effects 
of the high capillary pressure are well shown in the unusually full 
and prominent capillaries in the muscular layers. These vascular 
changes are perhaps most marked in the ileum, but while of the same 
general character, in some instances a well-marked congestion, with 
edema and diapedesis of red blood cells, also exists in the mucosa. 
In the mucosa of the ileum of the steer there is besides the unusual 
number of red blood cells a very pronounced invasion of eosinophile 
cells. In some cases there is a marked excess of polymorphonuclear 
leucocytes in the mucosa. 
SPLEEN. 
Changes in the spleen were not so pronounced as in the tissues 
previously mentioned. They consisted of a possible distention of a 
few cavernous veins and a few small areas of congestion and some- 
times the presence of considerable blood pigment. Guinea pig 35 
was of interest, as many of the endothelial cells show their phagocytic 
function containing one or more red blood corpuscles and indicating 
a certain degree of blood destruction. 
