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WM. T. GOTTHEIL. 
mic layers, and possessed of all the qualities of rapid atypical 
growth which characterize cancer cells as well as embryonal cells. 
Why such cells should remain quiescent for half a century, and 
suddenly spring into vigorous life—that, as well as many other 
points, the theory left in the dark. 
The feeling has of late years been gaining ground that the 
malignant new growths must be of parasitic origin ; that no other 
theory will explain their occurrence. A number of iuvestigators 
—Ballance and Shattuck, in England; Scheurlen and Schill, in 
Germany; Freire, in Brazil; and Rappin,in France,have busied 
themselves especially with the subject. Their results, however, 
are as yet decidedly divergent and inconclusive. 
Without going deeply into their experiments, we can sum¬ 
marize the results obtained as follows : 
Bappin’s experiments were valueless. The diplococcus that 
he thought he found was found also in cultures made from healthy 
tissues. 
Ballance and Shattuck worked more carefully, and with a 
great number of cases. Their culture experiments, on the whole, 
gave negative results ; only a small proportion of their specimens 
gave them micro-organic cultures. Nearly ninety tumors, in all, 
were used. Nevertheless, the experimenters still hold to the 
parasitic theory as the most probable one to explain malignant 
new growths. 
Scheurlen experimented with ten carcinomata of the breast. 
He found oval, greenish, shining bodies, which he called the 
spores of the carcinoma bacilli. The bacilli themselves could 
rarely be seen. He claims to have been successful in his cultures, 
and to have obtained bacilli containing oval, greenish, shining 
spores, identical with those obtained from the juices of the tissue 
itself. Inoculation experiments on dogs, etc., were, to say the 
least, inconclusive. 
Scheurlen’s researches have convinced a few competent judges, 
but the great majority believe his claim to have discovered the 
etiological factor of carcinoma to be premature. It is concern¬ 
ing the real nature of Scheurlen’s spores and bacilli that investi¬ 
gators are now busying themselves. 
