Item 6 comes with a heavy recommendation. The book is The Naturalist in Nicaragua by Thomas Belt. Writing to Sir J.D. Hooker, Charles Darwin said, "Belt I have read, and I am delighted that you like it so much; it appears to me the best of all natural history journals which have ever been published." Belt had surveyed plants and animals throughout Nicaragua, and this book ties in what he found to Darwin's theory of evolution. Offered is the "revised and corrected" second edition from 1888. $475.

Item 52 is Charles Waterton's Wanderings in South America, the North-West of the United States, and the Antilles, in the Years 1812, 1816, 1820 and 1824. Why Waterton only wandered during presidential election years is not clear. Perhaps they were as unpleasant then as they are now. This is an 1825 first edition of a classic travel book by a birder who described many species virtually unknown to the general public at the time. $650.

The website for Plaza Books is www.plazabooks.com. Their phone number is 707-546-3544.