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THE AMEBIC AN NATURALIST [Vol. XLVII 



and in each case there is a brief summary in the alternate lan- 

 guage. This is a great convenience to the French and English 

 reading public but it is not clear why German should have been 

 so rigidly excluded. A number of the papers were presented in 

 German but in each case these have been translated into French 

 with an English summary. 



Of the papers which attracted most attention at the conference 

 probably that of Miss Saunders on "The Breeding of Double 

 Flowers ' ' held first place. Miss Saunders 's results have since been 

 published elsewhere but their interest is sufficient to be noted 

 very briefly here. In the genus Matthiola there are two kinds 

 of single flowers — (1) the double-throwing and (2) the non- 

 double-throwing. The doubles are always sterile, so that doubles 

 must always come from single parents. Miss Saunders showed 

 that singleness is due to two factors, X and Y, and that in the 

 non-double throwing type these two factors are linked together. 

 Doubleness is due to the absence of either or both of these factors. 

 Now it further appears that in the double-throwing strains all 

 four possible combinations of these factors occur in the ovules 

 but "the pollen appears unable to carry X and Y either alone 

 or together." Thus we have in addition to the coupling or 

 reduplication a case of sex-linked inheritance which so far as the 

 writer is aware was the first case to be reported among plants. 



In a brief paper Professors Bateson and Punnett pointed out 

 that what they had formerly termed "coupling" and "repul- 

 sion" are in reality phases of the same phenomenon. In each 

 case the results are produced by a "reduplication" of those 

 gametes which represent the parental combinations. This is 

 another case of results which were new at the time of the con- 

 ference but which have become familiar to students of genetics 

 through other publications. 



A number of papers deal with the heredity and breeding of 

 cereals. Of these there may be mentioned one by Dr. Jesenko 

 upon a fertile hybrid between wheat and rye. This cross has 

 been made a large number of times but in every instance the Pi 

 plants were sterile. Dr. Jesenko succeeded in finding one plant 

 partially fertile and from this, F 2 and F 3 generations have been 

 grown. The interest in this work lies in the fact that the F 2 and 

 F 3 plants were fairly fertile. In this connection should be noted 

 the paper by Mr. Sutton, of England, on hybrids between the wild 

 pea of Palestine and the common commercial pea. In this species- 



