The scrapbook of drawings includes about 22 watercolors of insects, reptiles, and fish by Maria Sybilla Merian (1647-1717).
The album had belonged to Richard Bull, and along with those drawings and others, including one by William Hogarth, there are several verses in Bull’s hand and a letter from Walpole to Bull in which Walpole mentions Merian’s work (see the letter transcribed in the digitized Yale Edition of Horace Walpole’s Correspondence at http://images.library.yale.edu/hwcorrespondence/page.asp?vol=42&page=107&srch=merian's ) :