This is one of my favorite topics, and I'm glad that someone else has raised these questions again. I used to receive a catalog from a well-known commercial supplier of fruit trees. In that catalog, not only was the variation in clonally propagated material noted, but furthermore the variations were identified (somewhat confusingly to those of us used to the usual meaning of the term) as strains. For those of you not into this stuff, the term strain typically refers to seed propagated material (rather than clonally propagated material) which varies within only narrow limits. Or am I mistaken: is there a parallel history of usage of the word strain among those such as nurserymen and tissue culturists who deal with clomally propagated material? At any rate, as I pointed out in an earlier post, the meaning of the term clone seems to be changing. The older, seemingly original, meaning is being abandoned in favor of a meaning which emphasizes the purportedly absolute similarity of the elements which make up the clone. Yet as anyone who works with clonally propagated material knows, such absolute similarity is an illusion. These two different meanings not only introduce an element of ambiguity, but they are also in some respects mutually contradictory. Jim McKenney jimmckenney@starpower.net