- Deviating from the normal, perfect, or mature form;
having different forms at different stages of existence, or in
different individuals of the same species; -- applied especially to
insects in which there is a wide difference of form between the larva
and the adult, and to plants having more than one form of flower.
- Any one of numerous species of cestode worms belonging to
Taenia and many allied genera. The body is long, flat, and composed of
numerous segments or proglottids varying in shape, those toward the end
of the body being much larger and longer than the anterior ones, and
containing the fully developed sexual organs. The head is small,
destitute of a mouth, but furnished with two or more suckers (which
vary greatly in shape in different genera), and sometimes, also, with
hooks for adhesion to the walls of the intestines of the animals in
which they are parasitic. The larvae (see Cysticercus) live in the
flesh of various creatures, and when swallowed by another animal of the
right species develop into the mature tapeworm in its intestine. See
Illustration in Appendix.