54 PLANT HYBRIDIZATION BEFORE MENDEL 



into flower in the same year. Out of the 65 crosses reported in 

 the third 'Tortsetzung," the Verbascum crosses numbered 18, and 

 involved the species phoeniceum^ Thapsus^ lychnites, nigrum, 

 hlattaria and phlomoides. 



All of the Verbascum crosses proved sterile. The crosses Lych- 

 nites fl. alb. X phoeniceum, Blattaria fl. flav. X nigrum, Blat- 

 taria fl. flav. X phoeniceum, Blattaria fl. flav. X Lychnites fl. 

 alb., Thapsus X nigrum, Lychnites fl. alb. X Thapsus, were 

 carried on reciprocally, and are interesting as being identical in 

 the reciprocal crosses, although their sterility showed them to be 

 species-hybrids rather than variety-crosses. 



In describing the cross Verbascum blattaria fl. flav. X Verbas- 

 cum lychnites fl. flav., Kolreuter discusses the question, why one 

 or the other of the previously described hybrid plants should not 

 have sometimes arisen in the wild state, or, if such have not 

 arisen, wherein the obstacle lay for their production, in the case 

 of plants, which, for so many thousands of years, had lived in 

 proximity to one another. He remarks upon the fact that neither 

 in the older nor the later botanical writings is there a description 

 of any hybrid plant of this genus having arisen in the wild. The 

 essential reason, Kolreuter concludes, for the absence of such hy- 

 brids, lies in their total or very marked infertility. Concerning 

 Linnaeus' hybrid of Verbascum Lychnites X Thapsus, he ex- 

 presses no doubt as to the actual hybrid origin of the plant, in 

 view of the sterility of the plant, and the fact that the parents 

 had grown for years together in the same plot. 



Kolreuter concludes then that the principle still holds, which 

 was laid down in the "Vorlaufige Nachricht," that, in the natural 

 state of things and under the ordinary set of circumstances, hybrid 

 plants are with difficulty produced or can be produced in nature. 

 Admitting, he says, that a botanist should have the fortune to 

 find a true hybrid plant in the field, the question yet remained 

 whether such an accident could have arisen in a region where 

 the natural conditions had remained entirely undisturbed directly 

 or indirectly. For, he says, 



"true wilderness as it comes from the hand of Nature is one thing ; a 

 field, free, but in respect to a hundred things often very much altered 

 by the hand of man, is another." (p. 193.) 



Kolreuter goes on to remark upon the apparent fact that the 



