THE FOUNDATIONS OF PREHISTORY. 89
question, how could secretions which are poured into the blood
produce different results on the right and left sides of the body ?
It has indeed been held by some that the mere occurrence of
androgynous individuals, whether symmetrical or not, negatives
the idea that secondary sexual characters can be due to the
action of hormones. On the other hand, there is so much
evidence in other cases that hormones, or at any rate somewhat
similar substances circulating in the blood, do give the stimulus
for the production of such characters that further research on
this problem is evidently still required, particular attention being
paid to the evidence from androgynous individuals.
EXPLANATION OF THE PLATE
Daphnia pulex.
Fig. 1. Androgynous individual, right side, x 35.
Fig. 2. Do., left side, x 35.
Fig. 3. Head of normal male x 55.
Fig. 4. Do. female x 35.
Fig. 5. Antennule and rostrum of androgynous individual, left, x 160.
Fig. 6. Do. of normal female, x 160.
THE FOUNDATIONS OF PREHISTORY.
By S. HAZZLEDINE WARREN, F.G.S.
(A Presidential Address to the Club.)
THE Address that I had the privilege of giving to you last
year was largely concerned with a record of facts ; these
were chosen for a special purpose, namely to illustrate some
of the many pitfalls which lie in the path of the enquirer in the
field of prehistory. At the present time it is difficult for me to
undertake any work needing close application, so I hope you will
bear with me if I discuss in greater detail certain of the problems
that lie at the root of the subject.
The problems presented in different sciences have to be
approached by entirely different methods. For example, we
may separate the elements oxygen and hydrogen of which
water is composed, and we may verify that result by combining
them together again and turning them back into water. More-
over, we may repeat and re-verify those experiments as often
as we may wish.
Such methods are as inapplicable to the past events of pre-
history as they would be to history itself. We cannot verify the