CARCINOMA OF THF THYROID IN SALMONOID FISHES. 
497 
children, a flagellate disease which, when the patient was transferred to Rio Janeiro, 
he was able to transfer to the silky monkey by means of the barbeiro. The charac- 
teristic symptoms of the disease in the children were enlargement of the thyroid, the 
stupefied appearance of the child, and enlargement of the lympahtic glands. He also 
succeeded in inoculating guinea pigs with the flagellate organism by injecting the blood 
of the infected children. 
He divided the disease into an acute and a chronic form. The chronic form is char- 
acterized by hypertrophy of the thyroid affecting one or both of the lobes of the thyroid 
and frequently the isthmus. Even in young children the enlargement of the thyroid 
may be very marked. He says that in some regions the disease is very widespread and 
here infantilism and cretinism are very prevalent. All these individuals presented the 
characteristic enlargement of the thyroid. The histologic picture of the disease is in 
part an inflammatory reaction of the stroma of the thyroid with outspoken sclerosis. 
In such cases the alveoli are small and the lumen reduced. The colloid is usually 
decreased in amount and stains poorly. In the vesicles there appears to be desquama- 
tion and degenerative changes of the epithelium which fill the lumina of the alveoli. 
The islands of epithelium which normally lie between the vesicles appear to have been 
increased by proliferation, in some covering extensive areas. Large cysts filled with 
colloid characterize the last stages of the chronic form, with occasional calcification of 
the cyst wall. 
In cancer of various kinds intermediary carriers have been suspected. The well- 
known association of cancer in Bilharzia disease with the important trematode parasite, 
Distomum haematobium, is classic. Borrel in 1906 reported having found very frequently 
in mouse cancer, in the immediate neighborhood of or within the tumor, occasional 
small nematode worms. These, he did not think, were themselves in etiologic relation 
to the tumors, other than as possible carriers of a specific virus. This theory was 
strengthened in his mind by finding in the left kidney of a rat, which died of a cancerous 
tumor in the right kidney, a small cyst containing a very young cysticercus, which was 
identified as belonging to the Tsenia crassicola of the cat. Upon the membrane of this 
cyst, which was attached to the tissue of the kidney, he found a small tumor of identical 
structure to that of the larger tumor of the right kidney. 
In the second case, furnished him by Laveran, a rat died of a tumor of the liver 
of the size of an orange, in the exact center of which was found a cyst with a tumor 
growing out from it in all directions. This cyst contained a cysticercus which was 
again identified as belonging to the Tsenia crassicola of the cat. Microscopically this 
tumor was a large-celled sarcoma. Bipolar and multipolar karyokinetic figures were 
very numerous. This tumor proved to be transplantable and had produced large 
tumors for three or more generations. Borrel felt that the successful transplantation of 
this tumor strongly indicated that the cysticercus had carried with it a virus which it was 
possible to propagate with the cells. Finally he called attention to the possible relation 
of helminthia and cancer and felt that this hypothesis was in accord with the frequent 
tumors of the digestive tracts and the appendix. He thought that the endemic occur- 
