OF BlilOllPillC AND TllIMOllPlIIC PLANTS. 433 



which had been placed on the stigmas twenty-four hours previously, 

 and not a single pure Cowslip was produced. We thus see that 

 there is the closest agreement in all the above-specified and most 

 characteristic points between hybrid unions with their hybrid 

 offspring and illegitimate unions with their illegitimate offspring. 

 The parallelism in the two following relations is not so clear, 

 but apparently holds good. We know that when dimorphic and 

 trimorphic plants are legitimately fertilized the seedlings consist in 

 about equal numbers of the two or three proper forms. But we 

 have seen that when the long-styled Lythriim was illegitimately 

 fertilized by its own-form pollen, all the offspring, fifty-six in num- 

 ber, w^ere long-styled ; so it was with the fifty-two illegitimate 

 children and grand-children of the long-styled Primula sinemis ; 

 with the sixty -nine of P. vulgaris^ and, with the exception of four 

 short-styled plants, with the 152 illegitimate children, grandchil- 

 dren, great-grandchildren, and great-great-grandchildren of P. veris. 

 The exceptional case of the four short-styled plants may perhaps 

 be accounted for by an error, as previously explained, in the 

 method of fertilization. Lastly, from the self-fertilized long- 

 styled Pahnonaria officinalis eleven seedlings were raised, and 

 these were all long-styled. Dr. Hildebrand has recorded an 

 analogous case with the long-styled form of Oxalis rosea. With re- 

 spect to the sliort-styled form, when plants of this nature are illegiti- 

 mately fertilized by their own-form pollen, short-styled offspring are 

 generally produced in unnaturally large proportion*. In two in- 

 stances when one form of the Lythrum was illegitimately fertilized, 

 not by its own-form pollen,but by that of another form, the offspring 

 (thirty-seven in number) belonged to the two parent forms, but not 

 one to the third form, as would have occurred with a legitimate 

 union. From a third illegitimate union between the forms of Ly~ 

 thrum the offspring (forty in number) consisted of all three forms in 

 rather uneq^ual proj)ortions j but this union was much less sterile 

 than any other illegitimate union. From these various facts it is ma- 

 nifest that an illegitimate union seriously disturbs the natural and 

 proper proportional numbers of the two or three sexual forms. 

 Now if we turn to hybrid unions between species whicli have their 



• Since this ^japer was read before the Society, I have raised illegitimate set^d- 

 linga from both the long-styled and short-styled forms of Polygonum Fagopt/rum 

 or common Buckwheat. As yet only 49 seedhngs from the self-fertilized long- 

 styled form have flowered, and of these 45 are long-styled and four short-styled ; 

 so that the rule does not here hold quite so strictly as in the cases given in the 

 text. Of the 33 seedlings from the Felf- fertilized short-styled form, V.) are short- 

 styled and 14 are long-stvled. 



