Xo. G40] SHOETER ARTICLES AND DISCUSSION 461 



the bad iiaiiie to iiibrecdiiifr in the past, the less vigorous off- 

 spring fretiiu'iitly ivsiilting from inbreeding, although healthy, 

 were also L-onsidcrcd to bo valueless for further propagation and 

 were (luiddy disposed oi'. 



This is si ill llie belief and practise of live-stock breeders. 

 Tiiose who do iiot know tlie i)rineiples involved think that in- 

 l)r('f'(liii,<j: li;is pt'fniaiiently injured the famdies with such weak- 

 (Micil iiidividiKiIs. E(iuipped with the results of two decades of 

 oviu'iic iiiV('siiL;;ii ion. we can say, " No! this is not so. Nothi>i<j 

 has hu ,1 lost. These less vigorous inbred individuals of no ap- 

 parent woi'tli have potentially great value." A widespread re- 

 ception of this idea has possibilities of great practical outcome. 

 Not to see clearly the important distinction wliich there is here 

 between the present and former views is not to appreciate the 

 real progi-ess which the combined genetic research of twenty 

 years lias made along this line. 



D. F. JONKS 



.\X .\l'l>Ai;i:.\T CASK OK SO.MATIC SECREGATIOX 

 IX\'()L\ I.\(; TWO LIXKKI) FACrrORS^ 



