Teratology
the study of malformations or abnormal growths, animal or vegetable. Deformities of the animal kingdom may involve the whole body, as shown by the dwarf; may involve shape, as clubfoot or hairlip; may involve color, as in the albinos. Those of the vegetable world deal with abnormal forms, like the four-leaved clover; production of double-flowering plants; bulbous modification of the roots; the metamorphosis of the organs, etc., as well as changes in the form of plants brought about by the skill of gardeners and agriculturists.