2 works in one volume, small 4to (195 x 155 mm). First work: engraved title-page, 6 engraved plates; numerous in-text engravings. Second work: 11 engraved plates in the second work. 

Early Latin edition of the first work, FIRST LATIN EDITION of the second work, of the letters that were published in Dutch by Boutesteyn, a variant state of the first work with the title spelled correctly on the title-page and with some of the mis-paginations corrected.  With de Hooghe's Artemis frontispiece, dated 1685. With the full Latin text for letters 43, 42, 38, 28, 29, 30, 31, 35, 46, 47, 45, 48, 50, 51, and 52 (first work), and 53-60 (second work). Leeuwenhoek submitted several letters to Robert Hooke for presentation to the Royal Society of London, covering a range of investigations for animals, plants and minerals. Dobell 23A; Dobell 24; Wellcome III, p. 477; see lensonleeuwenhoek.net/timeline/tax/publications.