212 PLANT HYBRIDIZATION BEFORE MENDEL 



The most important reference to Mendel in the above is the 



often-cited remark under the genus Pisum : 



"Mendel's numerous crossings gave results which were quite similar 

 to those of Knight, but Mendel believed that he found constant number- 

 relationships between the types of the crosses." (p. no.) 



This Statement manifestly shows a merely superficial under- 

 standing of the real significance of Mendel's results. How far 

 short this understanding actually fell is revealed in the statement 

 immediately following: 



"In general, the seeds produced through a hybrid pollination preserve 

 also, with peas, exactly the color which belongs to the mother plant, 

 even when from these seeds themselves plants proceed, which entirely 

 resemble the father plant, and which then also bring forth the seeds of 

 the latter." (p. iio.) 



The facts of dominance, and of the difference in the significance 

 of cotyledon-color and seed-coat color, pass unnoticed. We have 

 here plainly the case of the inheritance of seed-coat color taken 

 for the entire case of seed-inheritance in peas, the dominance of 

 roundness of form discovered by Mendel being clearly overlooked. 



The next reference is to crossing in Phaseolus. 



"ph. vulgaris L. var nanus L. ? X multiflorus Lam. fl. coccin. $ was 

 produced artificially by Mendel." (p. ill.) 



Then follows a paragraph of fourteen lines, discussing in a 

 merely conventional manner the inconclusive results of the cross, 

 the color-characters of flowers and seeds alone being noticed. 



Mendel's statement with regard to his Phaseolus crosses fBate- 



son, p. 367) was evidently overlooked, to the effect that "the 



development of the hybrids, with regard to those characters which 



concern the form of the plants, follows the same laws as in 



Pisum,'' as well as his further suggestion regarding the matter of 



color-inheritance in the plant, as follows (p. 3^7) '• 



"Even these enigmatical results, however, might probably be explained 

 by the law governing Pisum, if we might assume that the color of the 

 flowers and seeds of Ph. multiflorus is a combination of two or more en- 

 tirely independent colors, which individually act like any other constant 

 character in the plant," 



the matter being then discussed analytically at length in Mendel's 

 characteristic form of presentation. 



It seems singular that the peculiarity of Mendel's form of state- 

 ment, and its apparent significance, should have been able to 

 escape Focke's attention. 



