244 



passed for the question of germ genesis and propagation to be con- 

 sidered as matter fitting only for the diversion of scientists," 

 ("^Lancet June 21 1884.) Osteo-Sarcoma, or what is called cancer 

 in cattle, is a disease affecting the lower jaw in most cases, and on 

 very rare occasions the upper jaw, is most frequently met with in 

 steers, cows, and bulls in the order named between the age of two 

 and six years The favourite side of origin of the disease is at the 

 second or third molar teeth. 



When first presenting itself , it causes an apparent thickening of 

 the bone, attended later on with a globular or ovoid swelling gradu- 

 ally enlarging beneath the skin. The swelling is most prominent on 

 the inner surface of the jaw. At first the skin moves freely over 

 the tumour, but in advanced stages it becomes adherent to the bone, 

 and is with some little difficulty removed or scraped, off. Should 

 the parts be struck and inflammation ensue, ulceration of the 

 skin takes place, exposing a raw surface, and at later stages, open- 

 ings or fistulae are formed, leading to cavities within the medulla of 

 the bone ; through these openings, a discharge of more or less pus 

 is continually taking place. Eventually, great pain is felt on masti- 

 cation, and as the bones become further involved, the teeth drop 

 out, ultimately, if not slaughtered, the beast perishes from ex- 

 haustion and emaciation. These tumours occupy months, and even 

 years in their development, the soft tissues become changed into a 

 dense mass of fibrous tissue, and the bone is converted into a 

 porous-body, large cavities enclosing thin bony plates. In order to 

 obtain a section of the bone, removal of one or two teeth is neces- 

 sary, and then it will be seen at once on sawing through the bone, 

 that the appearances presented are very different from those of 

 healthy bone. 



The specimens shown were one of the lower jaw, and two of the 

 superior maxilla, the disease in the last extending from the orbit, 

 and showing well the honey-combed appearance of the eroded bone. 

 In a healthy jaw, the boundary lines of compact or hard tissue and 

 soft spongy bone are well marked. In the diseased bone, the soft 

 spongy tissue at the root of the tooth, or in other words, the marrow 

 is broken up and subdivided by numerous trabeculse of bone which 

 surround cavities containing a soft, red pulp ; the outer hard casing 

 of bone is so expanded and invaded by these deposits, that the land- 

 marks of hard and soft are obliterated, and the substance of the 

 bone is partitioned into divisions or islets of various shapes, and 

 marrow and bone, or rather soft material and bone become intimately 

 intermixed. The effects of this disease may be seen in other organs 

 and parts of the body. In the lungs soft circumscribed masses vary- 

 ing in size from a pea to a mandarin orange may be seen. On dis- 

 section these yield a green soft pulp like substance. In the liver 

 white umbilicated deposits may be found of a triangular shape. 



In the intestines traces also may be found. A gland attached to 

 the intestine beneath the peritoneum yielded the same soft green 

 substance, which exuded after its envelope was cut into. In the 

 canal itself, just under the mucous membrane, and projecting into the 

 canal were several small nodosities larger than a pea causing ulcer- 

 ation of the mucous membrane, and disclosing on section the green 

 caseous material, spoken of before. Glands also in the vicinity of 

 the jaw have been found to be enlarged, and their contents would 



