xiv ECONOMICAL 165 



running the risk of losing it altogether, as is now so often 

 the case. 



The application of Mendelian principles is likely to 

 prove of more immediate service for plants than animals, 

 for owing to the large numbers which can be rapidly 

 raised from a single individual and the prevalence of self- 

 fertilisation, the process of analysis is greatly simplified. 

 Even apart from the circumstance that the two sexes 

 may sometimes differ in their powers of transmission, the 

 mere fact of their separation renders the analysis of their 

 properties more difficult. And as the constitution of the 

 individual is determined by the nature and quality of its 

 offspring, it is not easy to obtain this knowledge where 

 the offspring, as in most animals, are relatively few. 

 Still, as has been abundantly shown, the same principles 

 hold good here also, and there is no reason why the pro- 

 cess of analysis, though more troublesome, should not be 

 effectively carried out. At the same time, it affords the 

 breeder a rational basis for some familiar but puzzling 

 phenomena. The fact, for instance, that certain characters 

 often " skip a generation " is simply the effect of dominance 

 in F! and the reappearance of the recessive character in 

 the following generation. " Reversion" and " atavism," 

 again, are phenomena which are no longer mysterious, 

 but can be simply expressed in Mendelian terms as we 

 have already suggested in Chap. VI. The occasional 

 appearance of a sport in a supposedly pure strain is 



