TRIMORPHISM n.
ndividuals 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.), tha…
TUNICATA n.
A grand division of the animal kingdom, intermediate, in some respects, between the invertebrates and vertebrates, and by some writers united with the latter. They were formerly classed with acephalous mollusks. The body is usually covered with a firm external tunic, consisting in part of cellulose, and having two open…