The coccobacilliform bodies of fowl coryza were successfully cultivated in the fetal membranes of fertile eggs. Microscopic examination indicated growth in approximately 50 per cent of 94 eggs inoculated on the 3rd to 4th day of incubation. Growth was generally inhibited, however, in eggs inoculated on the 10th day. One strain of the specific bodies was maintained through 11 successive passages in 4 day eggs.
A more consistent growth of the coccobacilliform bodies was obtained in tissue cultures. One strain, originally isolated in November, 1935, has been carried through 100 successive subcultures at intervals of 1–3 days. The specific bodies fail to maintain their morphological identity for any length of time in this medium.
It is noted that growth of the coccobacilliform bodies in fertile eggs and in tissue cultures is not dependent on the presence of living cells.