All of the ebooks in these collections are included in the Discovery Search. Following these links allows you to use special features of each collection or narrow your search to a certain type of ebook.
Not just journals! Books at JSTOR includes hundreds of ebooks across disciplines. "Books at JSTOR are available exclusively in a DRM-free, unlimited-user model. The ebooks work just like the journals on JSTOR, with unlimited simultaneous use, downloads, and printing, and no need to log in or use special software."