SEMINAL VESICLES: The seminal vesicles and epididymis, especially the tail, seem to be the parts most subject to extensive pathological changes, and bacterial invasion. In most instances, diseased vesicles present gross manifestations recognizable on clinical examination, while on the other hand microscopic changes may be present in the absence of gross lesions. As diagnosed on physical examination, or even on post mortem examination of the tract, the various forms may be classified into: 1. _Acute Catarrhal Type_: In this form, the vesicles are usually enlarged, soft, and more or less reddened by hyperaemia. On physical examination of the animal, distinct flinching is produced when pressure is applied to the organ. Enlargement may even be absent in the early stages, and the diagnosis may be made from the extreme sensitiveness alone. 2. _Suppurative or Cystic Types_: In both of these types, the vesicles are usually enlarged, either uniformly, or, as is usually the case, in localized areas. The suppurative form may extend over the entire gland, forming one large encapsulated abscess, or on the other hand, it may take the form of variable sized abscesses with thick sclerotic, or thin fluctuating walls. Occasionally the abscesses rupture and discharge their contents into the rectum. Dr. Williams presented one case of this type. One vesicle was apparently normal, whereas the other was about five times larger than normal, and consisted of a dense outer capsule which was adherent to all surrounding parts. On dissection, it was found that the organ consisted of abscesses of various sizes, the larger one of which had ruptured some time previously into the rectum, leaving the distinct remains of an opening into that part. The cystic form may occur either with or without suppuration. One case came to my attention in which both vesicles were made up of abscesses of varying sizes as well as of a smaller number of cysts. Evidently the cysts were of the retention type, and were secondary to the pyogenic infection. 3. _Chronic or Sclerotic Type_: This form is characterized by a distinct firmness with or without marked enlargement. The condition may be accompanied by disease of the parenchymatous tissue or it may take the form of a chronic productive inflammation of the interstitial tissue. This inflammation may be simply a superficial thickening, or it may extend in between the lobules.