476 Syncotylous Races. 
towards the middle of the base line, the sweep of the 
curve would obviously have been a still more gradual 
one. We see, therefore, here as elsewhere, that the inter- 
mediate race or eversporting variety is far more suscep- 
tible to selection than the half race. 
ii. IMPROVEMENT OF A HEMI-SYNCOTYLOUS RACE. 
Like tricotyly, I regard syncotyly as a single ele- 
mentary character the external manifestation of which 
is subject to fluctuating variability. Completely fused 
cotyledons, which are the type occurring most abundantly 
(see Fig. 98), constitute the normal or typical structure, 
whilst the lower degrees of fusion and the bilateral unions 
are the minus and plus variants of the same series. 
One of the most important problems in the theory 
of mutation is to bring together the various expressions 
of the same elementary character in each particular case. 
The delimitation of such groups is often clear at once, 
but often it can only be reached by the actual observa- 
tion of the process of mutation. Still, the question is 
obviously a fundamental one, for our whole conception 
of affinities must rest on it, both in the question of species 
and in that of hybridization. We must therefore seek for 
methods which will lead to a solution of this problem. 
With regard to the present case we may start from 
the following discussion. If the hemi-syncotyls and 
amphi-syncotyls were representatives of distinct elemen- 
tary characters, we should expect to be able to isolate 
the corresponding races. The amphicotyls are too rare 
and too difficult to cultivate, on account of the disturb- 
ance in the growth of the plumule, to offer much prospect 
of success. Hemi-syncotyls, on the other hand, are well 
