What is "trimorphism"

Trimorphism \Tri*mor"phism\, n. [See Trimorphic.]

1. (Crystallog.) The property of crystallizing in three forms fundamentally distinct, as is the case with titanium dioxide, which crystallizes in the forms of rutile, octahedrite, and brookite. See Pleomorphism.

2. (Biol.) The co["e]xistence among individuals of the same species of three distinct forms, not connected, as a rule, by intermediate gradations; the condition among individuals of the same species of having three different shapes or proportions of corresponding parts; -- contrasted with polymorphism, and dimorphism.

   Heterogonous trimporphism (Bot.), that condition in which flowers of plants of the same species have three different lengths of stamens, short, medium, and long, the blossoms of one individual plant having short and medium stamens and a long style, those of another having short and long stamens and a style of medium length, and those of a third having medium and long stamens and a short style, the style of each blossom thus being of a length not represented by its stamens.

n. 1 (context crystallography English) The property of crystallize in three distinct forms. 2 (context biology English) The coexistence among individuals of the same species of three distinct forms, not generally connected by intermediate gradations.

In biology, trimorphism is the existence in certain plants and animals of three distinct forms, especially in connection with the reproductive organs.

In trimorphic plants there are three forms, differing in the lengths of their pistils and stamens, in size and color of their 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. These organs are so proportioned in length to each other that half the stamens in two of the forms stand on a level with the stigma of the third form. To obtain full fertility with these plants, it is necessary that the stigma of the one should be fertilized by pollen taken from the stamens of corresponding height in another form. Hence six unions are legitimate, that is, fully fertile, and 12 are illegitimate, or more or less unfertile. Wallace has shown that the females of certain butterflies from the Malay Archipelago appear in three conspicuously distinct forms without intermediate links.

In crystallography, trimorphism refers to the occurrence of certain forms in minerals which have the same chemical composition, but are referable to three systems of crystallization.