MEXICAN WHOBLED MILKWEED AS A POISONOUS PLANT. 11 



change had occurred in the epithehal cells of the convoluted tubules 

 and consisted of cloudy swelling. Other cells were present, singly 

 and in groups, the cytoplasm of which had an unusual affinity for 

 eosin. Such cells contained shrunken nuclei which stained darker 

 and more uniformly than normal. Other nuclei were very faint or 

 had entirely disappeared. The lumina in may places contained a 

 considerable cpantity of disintegrated cytoplasm and sometimes 

 free epithelial cell nuclei. In congested areas frequently epithelial 

 cells of the tubules contained considerable brownish granular pig- 

 ment. Granular material, pigment, and an abnormal number of 

 leucocytes were found in some veins. Some distended capillaries 

 in the sections from the kidneys of Sheep 595 were occupied by 

 hyalin areas wliich stained strongly with eosin. 



Other tubules than the convoluted, as the ascending limb of Henle, 

 showed similar though less pronounced changes. 



Heart. — The myocardium of the left ventricle showed changes like 

 those occurring in some of the A. gaUoides cases, but were not so 

 marked. In many areas the capillaries were distended with blood 

 and very prominent between the muscle fibers. The tissue was 

 mildly edematous. In most areas the muscle fibers had a less dis- 

 tinct cross-striated appearance and a more granular cytoplasm than 

 normal. A few minute hemorrhages appeared. Very few leuco- 

 cytes were present. The red blood corpuscles stained well and ap- 

 peared to be normal. 



Lungs. — There was a mild inflammation of the lungs. The capil- 

 laries were engorged and distended, in many places nearly filling 

 the alveoli. Numerous leucocytes, mostly polymorphonuclear, 

 were scattered tlu-oughout the tissue. Many epithelial cells of the 

 alveoli appeared swollen or vacuolated and their nuclei were irregu- 

 lar in outline. The epithelial cells of the l)ronchioles were swollen or 

 in the process of disintegration, the bronchioles containing much 

 granular material, many nuclei of exfoliated cells, and sometimes 

 erythrocytes. 



In some veins there were areas composed of normal and pale 

 erythrocytes, much finely granular material, and a considerable num- 

 ber of leucocytes, mostly polymorphonuclear. A considerable quantity 

 of brownish pigment was distributed throughout the sections. 



Thyroid. — Little that was abnormal was found in the thyroid 

 glands. This organ was not congested in either animal, though 

 some brownish pigment and pale erytlu-ocytes were found. In a 

 few capillaries the erythrocj'tes appeared to have fused, forming 

 hyalin thrombi. In the A. gaUoides cases this ghind was almost 

 always severely congested. 



Thymus. — Congestion had occurred in the thymus in each of the 

 two sheep, though this was most pronounced in the thoracic portion 

 of the gland of Sheep 595, where extensive hemorrhage into the 



