Symbionticism and the Origin of Species.

Normal plant and animal cells contain minute bodies known as mitochondria, to which have been attributed a variety of cell activities. Dr. Wallin has attempted to demonstrate the bacterial nature of mitochondria and to postulate a theory which he calls "symbionticism." This expression signifies a symbiotic relationship between mitochondria and living cells. This relationship is regarded as so close and so fundamental that it leads to the somewhat startling conclusion that symbionticism is the "fundamental principle controlling the origin of species." New species are assumed to have their origin in the fusion of mitochondria with the cells in which they are found, possibly through the formation of new genes. The experimental evidence in support of this theory is based on the author's published researches in which he claims to have demonstrated that mitochondria are bacteria. This conclusion is reached after finding bacteria in cultures containing embryonic liver tissue in a