No summary available.

Origin of domestic varieties. EB ascribes "abnormal" variations to man’s propagation of casual monstrosities; believes "normal" variations, e.g. European races of cattle, are a consequence of man’s selecting the choicest specimens. Gives examples of "abnormal" variations; they give rise to features that have no counterpart among possible wild progenitors. Divides domestic animals into those whose origin is known and those whose origin is unknown. Considers that the wild progenitors of nearly all domestic birds are known. Fowls and pigeons show many varieties but if propagated abnormalities are ignored each group can be seen to be variations of a single species, the ancestors of which can be recognised without difficulty. Discusses varieties and ancestry of the domestic fowl. Variation in the wild; the ruff shows exceptional variability; other species of birds show variability in size of individuals. Remarks that markings sometimes vary on different sides of the same animal. Comments on the want of regularity in leaf and petal patterns of some plants. Discusses domestic varieties of reindeer and camels. Origin of humped cattle. Reports the rapid spread of a snail in lower Bengal that was introduced as a single pair five or six years previously.

[CD’s notes are an abstract of part of this memorandum. Memorandum originally enclosed with 1760.]