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NORMAL SERUM OF SHEEP NO. 2. EMULSION OF AN H. S.
                                 AGAR CULTURE.

NORMAL SERUM OF PIGEON. EMULSION OF AN H. S. AGAR
                                          CULTURE.

NORMAL SERUM OF RABBITS Nos. 1 AND 2. EMULSION OF
                              H. S. AGAR CULTURE.

The agglutinating power of an animal's serum increases
during immunisation against H. S.

SERUM FROM A HILL BULL IN PROCESS OF IMMUNISATION.
                  EMULSION OF AN H. S. AGAR CULTURE.

SERUM FROM A HILL BULL IMMUNISED AGAINST H. S.
               EMULSION OF AN H. S. CULTURE.

Although the agglutinins in an animal's serum increase
with the immunising process, the immunising properties of
the serum are not dependent on these agglutinins, e.g.,—

An anti-H. S. serum from a protected hill bull agglu-
tinated strongly at 1/100 dilution.