308 The American Naturalist. [April, 
flourished at the expense of the healthy structures round them. 
Now any disease arising from degeneration or overgrowth of 
embryonic survivals, [such as the remains of the Wolffian 
duct in the female] sets at defiance all human precautions; 
the embryonic tissue is hidden, and no one can tell either when 
or why it begins to go wrong. If cancer owed its rise simply — 
and solely to an overgrowth of embryonic tissue, there was no 
hope but in an early, a thorough, an unsparing use of the 
knife; no stamping out of the disease could be hoped for or — 
thought of. All attempts to trace the disease to the action 
of bacteria failed. But during the last few months the patient, 
cautious, untiring labour of years of a number of distin- 
guished pathologists has enabled them to detect the existence 
of organisms in cancer, which resemble, in all that is known 
as yet of their life history, the Sporozoa; and more especially 
the Coccidium oviforme. (Leuckart), of the rabbit. 
sm; å shows 
1 4 1 
Blau ulal PAV eer , 
} + R M ee 
Fig. 1.—a, Coccidium g cay 
condensation of the protoplasm into one sphere, after two days’ growth 
external to body ; c, division of the single sphere into four daughter spher- 
ules, after four days’ development; d, an empty ruptured cyst. (From 
photographs x about 500.) 
The whole life cycle of Coccidium oviforme is now known; 
its discovery has been the work of more than thirty years, 5° 
that there is no reason for discouragement if some stages of the 
life history of the Coccidium found in cancer still elude 
research. 
Dr. Galloway after describing the symptoms of co 
infection in the rabbit, begins with the life of the pro 
after it leaves the body. “The organism” he says 
escapes from the alimentary canal consists of a firm t 
ccidian 
toz00D 
“as it 
ranslu- 
