100 AMERICAN BREEDERS MAGAZINE. 



own have grown out of the conception, first presented by myself 

 two years ago, that what may appear to be a uniform variety of 

 Indian corn is really a series of very complex hybrids involving 

 numerous distinct biotypes, 6 which may be isolated from their hybrid 

 combinations by self-fertilization and which owe their smaller size and 

 inferior yielding qualities, not to any injurious effect of inbreeding 

 as such, but to the fact that self-fertilization gradually results in their 

 reduction to a pure homozygous state. They are thus deprived of 

 the stimulus which had been derived from crossing with other biotypes. 



It appears that my paper of two years ago was unknown to Mr. 

 Collins, although it was read in Washington and published in the 

 Annual Report of the American Breeders Association in 1908. As 

 Dr. East and I have both performed many experiments which have 

 led us to place great confidence in the practical importance of the 

 discoveries of Mendel, De Vries, and Johannsen, it is interesting 

 to read in Mr. Collins's paper that these new results from the scientific 

 side are "particularly dangerous" when applied to corn breeding. As 

 Dr. East and I by the application of the newer biological conceptions 

 have arrived at practically the same method which Mr. Collins recog- 

 nizes as necessary for the best results in corn breeding, it should 

 become evident to him that there is no such danger as he fears in 

 the application of the latest scientific results to practical work. 



The crossing of relatively homozygous strains or of distinct 

 biotypes in corn in order to secure the stimulus of hybridity, as 

 advocated by Dr. East and myself, involves a much more definite 

 conception, however, than that suggested by the tenn "broad breeding." 

 The idea of hybridization between distinct strains or between biotypes 

 calls for the use each year of those two parental strains or biotypes 

 which careful tests have shown 'to result in the greatest capacity for 

 yielding an excellent F (first generation hybrid) progeny. Although 

 Mr. Collins advocates a method which is essentially identical with 

 that proposed by Morrow and Gardner fifteen years ago and which 

 has been invented anew by Dr. East, the idea of broad breeding would 

 logically require the working in of a new variety or strain each year, 

 instead of going back to the same relatively inbred strains for each 

 successive crop. In other words, while Mr. Collins has suggested a 

 splendid method of corn breeding, it is not one which corresponds 



6 A biotype is a group of individuals which do not differ from one another 

 in any hereditary quality, and which therefore constitute a pure race. 



