Growths of this nature, even those which, like tubercle and cancer, are frequent in the brain, are very unfrequent in the spinal cord.

a. Tubercle I have observed only in combination with other advanced tuberculoses. Its principal seat is the cervical or lumbar part of the cord, where it sometimes occupies the white fibres, sometimes the gray substance. As in the brain, it leads to inflammation (red softening) and to yellow softening. I have never seen a tuberculous cavity in the cord. Sometimes several tubercles are grouped together, none exceeding the size of millet- or hemp-seed; at other times only one exists, which is of large dimensions equalling a pea or a bean.

b. Exclusively of several cases of circumscribed callous induration of the white columns, as to the cancerous nature of which I am still in doubt, I have met with but one case of cancer of the cord. It was a solitary nodule of medullary cancer. Ollivier mentions several examples of diffused carcinomatous growths, as well as of so-called colloid cancer.

c. Among the entozoa, I have repeatedly seen the cysticercus in the cervical portion of the spinal marrow. The acephalocyst sacs, so far as has been observed, have no connection with the cord, their nidus is even outside the dura mater. In one case the cyst forced its way into the canal of the arachnoid.