Vie CONG. INTERN. REPROD. ANIM. INSEM. ARTIF., PARIS, 1968, VOL. II

Further investigations are required before a
theoretical explanation of the specific kind of
deviation can be given, but reciprocity law failure is
now a well established fact, in agreement with what had
to be expected from the temperature-dependence of light
sensitivity, demonstrated in our previous investigat-
ions (3,4).

We can now with even more confidence predict the
existence of an intermittency effect, i.e. that the
biological effect produced by an exposure given in a
number of discrete instalments will be different from
that produced by a continuous exposure of the same
energy.

(1) R.W. BUNSEN and H.E. ROSCOE, 1859.Ann.Physik 108:193.
(2) C. VAN DUIJN Jr., 1961. Nature (Lond.) 189:76=78.
(3) C. VAN DUIJN Jr., 1967.Ann.Biol.anim.Bioch.Biophys.
T: 331-342.
(4) C. VAN DUIJN Jr. and J.H. VAN LIEROP, 1966.
Nature (Lond.) 211: 1313-1315.
E. KRON, 1913. Ann.Physik 417 751.
C. NORMAN, E. GOLDBERG and I.D. PORTERFIELD, 1962.
Exp.Cell Res. 28: 69-84.
R. RIXMENSPOEL, 1957. Experientia 13: 124.
R. RIKMENSPOEL, 1957. Thesis, Utrecht University.

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