of Heredity 29 



allelomorph, and we can speak of the integral characters 

 which constitute it as hypallelomorphs. We ought to write 

 the heterozygote (A A' A"...) B and the gametes produced 

 by it may be of the form A, A', A", A'",...B. Or the 

 resolution may be incomplete in various degrees, as we 

 already suspect from certain instances ; in which case we 

 may have gametes A, A' A", A 1 " A"", A'A"A\...B, and 

 so on. Each of these may meet a similar or a dissimilar 

 gamete in fertilisation, forming either a homozygote, or a 

 heterozygote with its distinct properties. 



In the case of compound allelomorphs we know as yet 

 nothing of the statistical relations of the several gametes. 



Thus we have the conception 



(5) of a Compound character, borne by one gamete, 

 transmitted entire as a single character so long as 

 fertilisation only occurs between like gametes, or is, 

 in other words, "symmetrical," but if fertilisation 

 take place with a dissimilar gamete (or possibly by 

 other causes), resolved into integral constituent- 

 characters, each separately transmissible. 



Next, as, by the union of the gametes bearing the 

 various hypallelomorphs with other such gametes, or with 

 gametes bearing simple allelomorphs, in fertilisation, a 

 number of new zygotes will be formed, such as may not have 

 been seen before in the breed : these will inevitably be 

 spoken of as varieties ; and it is difficult not to extend the 

 idea of variation to them. To distinguish these from other 

 variations which there must surely be we may call them 



(6) Analytical variations in contradistinction to 



(7) Synthetical variations, occurring not by the 

 separation of pre-existing constituent-characters but 

 by the addition of new characters. 



