Many of the islanders, however, show signs of hybridism.
The hybridism of the Abyssinians is reflected in their political and social institutions, and especially in their religious beliefs and practices.
Nevertheless, in exceptional cases modified growths, termed " grafthybrids," have been obtained which have been attributed to the commingling of the characteristics of stock and scion (see Hybridism).
Egtfally great gaps, however, may exist between males and females, between climatic phases or summer and winter forms. The attempt to find a physiological criterion has similarly failed; many forms that have been universally accepted as true species produce fertile hybrids (see Hybridism).
