An unreduced gamete of the 2n = 22 zeylanicum
in combination with a normal gamete of the
standard type would give a triploid with 3n= 33
(AA+ B). From such a hybrid, gametes could
be produced which were A+ 4 of the B complement.
Fusion of gametes of this type would
produce 22 A+ 8 B and the B members would be
present as homologous pairs. This model is
perfectly feasible and perhaps the best explanation
of the present results. There seems to be
no way in which one can adequately explain the
evolution of the 2n= 30 type from the 2n= 22
type without considering a donor of the extra
chromosomes. Meiotic analyses of a possible
hybrid between the 2n = 30 and the 2n = 22 types
could have given information on the origin of the
2n = 30 type.