2 8o POPULAR SCIENCE MONTHLY. 



in the progeny of the hybrids. The seed of each hybrid plant was 

 kept separate and sown as a plat. In three plats from a cross between 

 Valley (J 1 ), a bearded variety, and Little Club (5), there was an 

 average of 25.7 per cent, of bearded plants. Eleven plats of the 

 reciprocal cross averaged 25.2 per cent, beards. Six plats of a cross 

 between Little Club and Emporium gave bearded plants to the extent 

 of 24.6 per cent.; three plats of Lehigh X Red Chaff, 25.9 per cent.; 

 and seven plats of Turkey X Little Club, 30.8 per cent. In the 

 last example there were two aberrant cases, the remaining five lying 

 between 25 and 29 per cent. 



Much evidence of a similar nature has been brought forward by 

 De Vries, Correns, Bateson and others, in addition to that given by 

 Mendel. These investigators worked with widely different groups of 

 plants and animals. 



Thus far, no one has shown definitely that Mendel's theory is 

 inapplicable to a single case. Correns, however, mentions hybrids 

 which do not behave exactly as called for by theory, but I am not 

 sufficiently familiar with the details concerning them to discuss them 

 here. In my own work I found that the color of the chaff and the 

 length of the head behave in a manner most easily explained by 

 a modification of Mendel's theory. Instead of the pair of opposite 

 characters, long heads and short heads, separating completely on the 

 formation of pollen and ovules, they seemed to separate in all possible 

 proportions, giving in the next generation a series of plants having 

 heads of every possible gradation of length between those of the 

 two parents, and even extending in both directions beyond the parents. 

 In my work I arbitrarily separated the hybrids into three groups 

 long, semi-long and short heads. As this separation was entirely 

 arbitrary, the results are very irregular, and the original figures do 

 not represent very accurately the actual facts with reference to this 

 character. Exactly the same thing occurred with reference to color 

 of chaff. I have not yet had the opportunity of examining the 

 third generation of these hybrids, so that it can not yet be stated 

 definitely that they really form an exception to Mendel's law. 



As is the case with any startling discovery, we are apt either to 

 minimize its importance or to extend its application much beyond 

 legitimate bounds. I fear I shall be accused of the latter. But 

 this new thory is so suggestive and offers a rational explanation to 

 so many hitherto enigmatical phenomena, that a few suggestions 

 as to its possible application can do no harm. 



