8 The Significance of H oriicnltural Varieties. 



yellow or even white leaves or seedlings are by no means 

 rare in variegated varieties. But the resemblance is only 

 superficial. The green minus variant of the variegated 

 type does not belong to the original species, nor the yel- 

 low plus variant to the golden variety; as may often be 

 seen by sowing the seeds of such extreme types. 



I propose to call such varieties intermediate races, and 

 if neither of the two antagonistic characters preponder- 

 ates too much over the other, balanced races or ever- 

 sporting varieties^ (see § 3). 



If we attempt to make a statistical study and graph- 

 ical description of the variability in such intermediate 

 forms we must obviously not expect such simple and 

 straightforward curves as those which describe the var- 

 iability of normal characters (Vol. I, p. 48). In prin- 

 ciple we may expect to obtain figures which simultane- 

 ously exhibit. the two magnitudes — that is to say com- 

 pound curves such as have been studied by Ludwig^ 

 Bateson, Pearson, Davenport and others. It is evi- 

 dent that they will present very different forms according 

 to the mutual proportion of the two characters (see be- 

 low §§ 3-5). At the same time it is clear that in such 

 cases selection may lead to special results which will often 

 be due to the impossibility of transgressing the characters 

 of the two limiting types (see § 5 and Fig. 3). 



The two following generalizations may be derived 

 from the facts we have been discussing. 



1. Some horticultural varieties ozve their existence to 

 a single new character. These are usually not more vari- 

 able than the original species and as a rule just as con- 

 stant from seed. Very frequently the novelty consists 

 in the loss or latency of a character of the parent spe- 



* See Species and Varieties, Their Origin by Mutation, p. 309. 



