Cloning was first published in 1985. Minnesota Archive Editions uses digital technology to make long-unavailable books once again accessible, and are published unaltered from the original University of Minnesota Press editions.

In this, the first published monograph devoted exclusively to the cloning procedure, Professor McKinnel reviews the results obtained in nuclear transplantation experiments with amphibia and provides an extensive discussion of the methodology used. He explains that while biologists generally use the word "cloning" to refer to the production of multiple genetically identical individuals, he uses it in a more general sense to refer to one or more individuals produced by nuclear transplantation. He points out that results obtained from the cloning technique are often oversimplified and are sometimes misleading, and he discusses conditions which may lead to success or failure in achieving cloning. The extensive section on methodology describes, sufficiently to instruct new comers to the technique, the preparation of microscopic tools, micromanipulation procedure, the husbandry and reproductive biology of amphibians, dissociation of donor cells, and the activation and enucleation of mature ova. The work is generously illustrated with halftones and line drawings.