Thanks so much for that apt comment. Yes, authorship is often reserved for the name cited first. However, I believe Wallace's claim to credit is not based on the authorship of this paper. It is based on the considerable work he did independently in identifying and categorizing species. (See, for example, the Wallace Line.) He seems to have been quite prolific and insightful in that regard. Of course, I only just learned about him so I am hardly an authority.