Not until men entered that closed system could humans escape biology by becoming the psychologically trimorphic family: mother-father-baby. ❋ Mike L (2007)
The flowers are trimorphic with long, short or mid-length styles. ❋ Unknown (1987)
If Natural Selection could not accumulate varying degrees of sterility for the plant's benefit, then how did sterility ever come to be associated with _one cross_ of a trimorphic plant rather than another? ❋ James Marchant (N/A)
The groundwork of the acquirement of such peculiar fertility (for what you say about any other distinct individual being, as it would appear, sufficient, is very true) rests on the stamens and pistil having varied first in relative length, _as actually occurs_ irrespective of dimorphism, and the peculiar kind of fertility characteristic of dimorphic and the trimorphic plants having been ❋ James Marchant (N/A)
To Sprengel, and specially to Darwin, physiologists are indebted for the demonstration of the relation of di - and trimorphic flowers to fertilisation. ❋ Maxwell T. Masters (N/A)
The same excellent observer has demonstrated that the di - and trimorphic forms of _Primula_, of _Linum_, _Lythrum_, and other plants -- forms differing mainly in the relative length of the stamens and styles, are also connected with striking differences in the number of perfect seeds produced. ❋ Maxwell T. Masters (N/A)
If Natural Selection could not accumulate varying degrees of sterility for the plant's benefit, then how did sterility ever come to be associated with one cross of a trimorphic plant rather than another? ❋ Marchant, James (1916)
The groundwork of the acquirement of such peculiar fertility (for what you say about any other distinct individual being, as it would appear, sufficient, is very true) rests on the stamens and pistil having varied first in relative length, as actually occurs irrespective of dimorphism, and the peculiar kind of fertility characteristic of dimorphic and the trimorphic plants having been secondarily acquired. ❋ Marchant, James (1916)
This will perhaps be made more fully apparent by an illustration; we may suppose that a botanist found two well-marked varieties (and such occur) of the long-styled form of the trimorphic Lythrum salicaria, and that he determined to try by crossing whether they were specifically distinct. ❋ Unknown (1909)
With trimorphic species six unions are legitimate, or fully fertile, and twelve are illegitimate, or more or less infertile. ❋ Unknown (1909)
We may, however, infer as probable from the consideration of dimorphic and trimorphic plants, that the sterility of distinct species when crossed and of their hybrid progeny, depends exclusively on the nature of their sexual elements, and not on any difference in their structure or general constitution. ❋ Unknown (1909)
With trimorphic plants there are three forms likewise differing in the lengths of the pistils and stamens, in the size and colour of the pollen grains, and in some other respects; and as in each of the three forms there are two sets of stamens, the three forms possess altogether six sets of stamens and three kinds of pistils. ❋ Unknown (1909)
The facts given on the sterility of the illegitimate unions of dimorphic and trimorphic plants and of their illegitimate progeny, perhaps render it probable that some unknown bond in all cases connects the degree of fertility of first unions with that of their offspring. ❋ Unknown (1909)
So it is with the reciprocally dimorphic and trimorphic plants previously alluded to. ❋ Unknown (1909)
Analogy from the consideration of dimorphic and trimorphic plants clearly leads to the same conclusion, for when the forms are illegitimately united, they yield few or no seed, and their offspring are more or less sterile; and these forms belong to the same undoubted species, and differ from each other in no respect except in their reproductive organs and functions. ❋ Unknown (1909)
It is possible to raise from dimorphic species, both long-styled and short-styled illegitimate plants, and from trimorphic plants all three illegitimate forms. ❋ Unknown (1909)
Lastly, many hybrids are profuse and persistent flowerers, whilst other and more sterile hybrids produce few flowers, and are weak, miserable dwarfs; exactly similar cases occur with the illegitimate offspring of various dimorphic and trimorphic plants. ❋ Unknown (1909)
No one until lately would have imagined that in dimorphic and trimorphic plants the different lengths of the stamens and pistils, and their arrangement, could have been of any service, but now we know this to be the case. ❋ Unknown (1909)
The infertility which may be observed in various dimorphic and trimorphic plants, when they are illegitimately fertilised, that is by pollen taken from stamens not corresponding in height with the pistil, differs much in degree, up to absolute and utter sterility; just in the same manner as occurs in crossing distinct species. ❋ Unknown (1909)
