Paul, thanks for trying to help but I'm afraid your message did not make things any clearer for me... Noble Proctor's book Manuel of Ornithology goes into some detail about avian topography, and I see that primaries are indeed numbered backwards from the outermost to innermost, but why then do both the Seabirds(Harrison) and Gulls(Grant) books choose to number them the other way around. Gulls are certainly confusing enough without adding another terminology hurdle. Perhaps in the first edition of Grant's Gulls he has them numbered the other way? I don't know, since I only recently purchased the newer second edition, paperback 1997. Still trying to find the answer to this puzzle... Warblerick@aol.com Rick Sussman Ashton,MD