The Atlantic Seaboard


    In the 88o's and 1890's many variations in bacterial and colonial
 morphology were described; in fact, sharp controversy arose between
 men such as Cohn and Koch, who held a monomorphic theory, and
 other observers, who saw in these variations only phenomena similar
 to those in higher plants and animals. The causes for these changes
 have only gradually come to light and are still only partially under-
 stood. We have already described the studies of Smith and Reagh, who
 found the basis of certain rough and smooth variations in some enteric
 organisms. The broad, far from clear term, microbic dissociation has
 been used and presented in detail by Philip B. Hadley.
   Among the pneumococci, changes in morphology, growth characters,
 and virulence were well described by Kruse and Pausini as early as
 1891. Indeed they tied capsule formation to virulence. Many investi-
 gators, especially Avery and his associates at the Rockefeller Insti-
 tute, have added results so striking that we may be pardoned for look-
 ing over the fence beyond our period. Bacterial genetics, mutations,
 transmissible lysis all come into the confused picture that is gradually
 becoming less confused. Griffith,23 of the British Ministry of Health,
 made the next startling observation, finding that mice injected with a
 small amount of living rough unencapsulated organisms of Type I, for
 example, together with a large inoculum of heat-killed Type II smooth
 encapsulated cells, frequently succumbed to infection, and from the
 heart's blood of these animals, pure cultures of Type II were obtained.
 Many doubted this transformation thinking that it must be an error in
 technique, but it was soon confirmed both abroad and in this country.
 A still more startling step came later when Avery, MacLeod, and
 McCarty isolated the transforming substance of pneumococcus Type
 III, a highly polymerized deoxyribonucleic acid.
   Oswald T. Avery (1877-1955), leading man in these dramatic dis-
coveries, was warmly admired and loved by his many colleagues. He
was a small man physically, never robust, with a large head and a de-
lightfully modest, shy manner, not altered by the world fame that came
to him, yet conscious of the importance of the work and its broad impli-
cations. He never married. His distinguished researches into the struc-
ture and serology of pneumococci and the fostering of immunochemis-
try, especially with his colleagues Michael Heidelberger and W. F.
Goebel, brought high honors. He held the presidency in all the societies
allied to his studies; he was an honored member of the Royal Society
and of our own National Academy of Sciences; he was a member of


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