PLANT HYBRIDIZATION BEFORE MENDEL 163 



another in respect to fertility, and especially in the structure of certain 

 parts, now approximating more to the father, now to the mother." (p. 25.) 



Wiegmann's independence of traditional authority is witnessed 

 in his contradiction of the view of "the great Linnaeus," that 

 hybrids resemble the mother in the fertilization apparatus, and 

 the father in foliage and habit. Instead, he says : 



"The change through the foreign fertilizing pollen shows itself in very 

 different parts in different plants ; in the anther-filaments, in the in- 

 florescence, in the form, color, and odor of the corolla, in the height of 

 the stem and its divisions, in the form and outside covering of the leaf." 

 (p. 23.) 



Referring to the then general assumption that hybrids (of the 

 Fi generation) occupy a mid-position with respect to their char- 

 acters between the two parents, he says : 



"In many cases this does not occur, but either the color of the father 

 or that of the mother shows itself alone dominant (herrschend) in the 

 hybrid. The same also obtains among animal hybrids ; the two colors may, 

 through mingling, give an intermediate one, but in just as many cases 

 the one only prevails. Plant hybrids therefore unite in themselves in part 

 the peculiarities of the father, in part those of the mother, whereby they 

 approach now the maternal, now the paternal form." (p. 21.) 



Regarding the matter of dominance, Wiegmann further inci- 

 dentally remarks upon the case of the crossing of two species of 

 Dianthus, where "the form of the father has almost entirely 

 suppressed that of the mother." (p. 22.) 



For present-day genetics, one of the most interesting points in 

 Wiegmann's report is his discussion of the immediate effect of 

 the pollen in the case of leguminous plants. According to his 

 statement : 



"Even immediately after fertilization, an alteration arising in the form 

 and color of the seed, and in the form and size of the pods, is especially 

 unmistakable in the case of the leguminous plants, although otherwise 

 all fruits and seeds of hybrid plants from other families have never 

 shown themselves to me to be different from those of the mother plants." 

 (P- 23.) 



And again : 



"The principle expressed by Gartner, that the influence of foreign pol- 

 len changes nothing in the form and external character of the fruits and 

 seeds of the mother plants, should, according to my investigations, un- 

 dergo a modification in the case of Diadelphia {Leguminosae) , since, in 

 the case of these, the foreign pollen exerts an immediate effect upon the 

 color and other characters of the fruits and seeds." (p. 29.) 



In the case of Phaseolus, he says : 



