130 PLANT HYBRIDIZATION BEFORE MENDEL 



"The first and the most important of all is that the singular beings 

 which result from the cross-fertilization of two different types, far from 

 being condemned to absolute sterility, are frequently endowed with the 

 faculty of producing seeds capable of germination." (i, p. 129.) 



An essential feature in Naudin's paper, of high importance 

 from our present standpoint, is the independent behavior of 

 characters in a cross, referred to by the Academy committee as 

 follows : 



"Not content with responding by numerous experiments to the ques- 

 tions propounded by the Academy, the author . . . has sought to throw 

 light upon several points, some obscure, others not yet studied, in the 

 history of hybrids. He has confirmed that which Sageret already knew, 

 that in a hybrid the characters of the two parents are often shown, 

 not blended but approximated, in such fashion that the fruit of a 

 Datura hybrid, born of two species, the one with a smooth, and the other 

 with a spiny capsule, presents smooth surfaces in the midst of a surface 

 generally spiny. This 'disjunction,' as it is called, is explained according 

 to him by the presence in the hybrid of two specific essences, which tend 

 to be separated more or less rapidly the one from the other. He even 

 sees in this disjunction the true cause of the return of fertile hybrids 

 to the specific types from which they came." {ib., p. 131.) 



It is further of great interest to note that the seeds gathered 

 from the smooth side of the capsule reproduced only the smooth- 

 capsule form, Datura laevis, while those taken from the spiny 

 side gave rise only to the spiny form, Datura stramonium. In Ver- 

 lot's paper, yet to be discussed, further instances of this type of 

 segregation will be found. 



Naudin stated more clearly and definitely than others had 

 hitherto done the fact of the general uniformity of the hybrid 

 offspring of the first generation, and the diversity of form, with 

 partial reversion to, or, as we would now put it, the reappearance 

 of, the parental types, in the second hybrid or F2 generation. His 

 language is as follows : 



"Finally, one may say that the hybrids of the same cross resemble one 

 another in the first generation as much, or almost as much, as the indi- 

 viduals which come from a single legitimate species." (4c, p. 188; Comp- 

 tes Rendus, 4d, p. 839.) 



In contradiction to the results derived by Sageret from his par- 

 ticular set of experiments, Naudin asserts the generally inter- 

 mediate nature of the first generation hybrid condition : 



"All the hybridologists are in accord in recognizing that the hybrids 

 (and it is always a question of the hybrids of the first generation) are 

 mixed forms, intermediate between those of the two parent species. This 

 is, in fact, what takes place in the immense majority of cases; but it 



