It was inevitable that Pakenham, an historian of Africa with a penchant for the world's most striking and bizarre trees, would discover the baobab. In this followup to Remarkable Trees of the World and Meetings with Remarkable Trees, he focuses on the tremendous, twisted boabab trees of Africa, Madagascar and Australia. Of the world's eight species, six are found in Madagascar. With 60 large-format color photographs.  (NAT71, $19.95)