332 Explanation of Inheritance 
polation, quite analogous to that of which we have 
spoken above, of three or more groups of specific poten- 
tial elements in the whole series of germinal elements, 
with the result that the activation of one of these groups 
prevents that of all the others. Thus each form of the 
polymorphous kind would have its own characters which 
arise entirely by the inheritance of characters acquired 
through functional adaptation. 
It is nevertheless to be remarked that a few forms 
of certain polymorphous species are possibly to be 
ascribed also to the circumstance that a few groups 
among all the specific potential germinal elements of the 
entire series are hindered in their activation, not so much 
by properly ontogenetic conditions which depend upon 
the development of other characters, as rather by quite 
general conditions of temperature, nutrition, etc., so that 
thus the form in which hese groups are not activated, 
differs from the principal form only through the absence 
of some single character. This might be the case, for 
example, in the working bees and generally in the neuters 
of many insects, the explanation of which would thus 
be quite similar to that which Spencer gives in his polemic 
with Weismann. But evidently these forms with incom- 
plete development represent essentially only a special case 
of the preceding supposition. 
We can thus say also that the fundamental principle 
to which centroepigenesis has recourse in order to explain 
sexual dimorphism and polymorphism in general, that 
is, to explain how it comes about that the development 
of certain characters prevents that of certain others 
which remain latent, is still the same principle which 
has already served to explain the fact that ontogenetic 
