422 BOVINE PATHOLOGY. 



The question may arise as to the propriety of use of the 

 flesh of a cancerous animal for food ; if the patient 

 presents marked constitutional changes the carcase ought 

 to be at once condemned. But we have no proof of 

 cancer of the lower animals being communicable to man, 

 and it is highly improbable that a disease which can 

 scarcely be communicated by inoculation to another animal 

 of the same species would be produced by ingestion of 

 the flesh as food. Thus, the use of such flesh must be 

 sanctioned, but we must remember that this may possibly 

 be a source of human disease, and should make this a 

 matter for testing by observations and experiments. 

 Next in importance to the true cancers must be placed the 

 Sarcomata — tumours composed of embryonic tissue. 

 They are generally described as cancer, but are dis 

 tinguishable from it by the nature of their elements. 

 These vary considerably in their characters, but in all 

 cases they present the distinctive features of new and 

 imperfectly formed tissue. This generalised nature often 

 makes them seem malignant, for they may grow in 

 tissues of different kinds, and are frequently seated in 

 the lymphatic system. They tend to recur, for since 

 they are similar in nature to the parts in which they are 

 found, the generating tissue cannot be completely re- 

 moved. They are not frequent in the ox unless the 

 disease known as Osteosarcoma or Spina ventosa is to be 

 considered under this heading, as it probably ought to be. 

 It appears as a swelling of the face, which is hot and 

 painful, opposite the molar teeth either of the upper or 

 lower jaw. This increases in size but does not materially 

 prevent the animal from feeding. The patient is generally 

 young, and the disease seems to be more prevalent in 

 some parts of the country than in others. As it progresses 

 the molar teeth become loose, and softening of the swelling 

 occurs in spots, which ultimately burst, and there is then 

 a profuse discharge of a gelatinous or purulent character. 



Post-mortem examination shows disorganization of the 

 bone apparently of a colloid nature. The swollen bony 

 structure is arranged in bands and layers, the spaces 



