On the Antigenic Structure of the Bacterial Spore

capable of inducing the formation of specific antibodies and give no evidence in agglutinin-absorption experiments of possessing antigens related to vegetative cells. In contrast to these findings is the work of Krauskopf and McCoy (1937), who, using alkali-treated spores of Bacillus niger to prepare antiserum, found a serological relationship of spores to vegetative cells. They concluded that spores did not possess antigenic factors not found in vegetative cells. The present series of experiments has been directed toward a more complete understanding of the spore in its antigenic relation to its mother cell and toward the reconcilia-tion of the data of Krauskopf and McCoy with the experience of other investi-gators. Cross agglutination between spores from various species, which would require a complex antigenic structure for the spore, has been denied by Bekker (1944). On the other hand, Defalle (1902) and Lamanna (1940b) have reported some evi-dence suggestive of such cross reactions, a finding which is developed further in this paper.