Nepenthes ×williamsii Hort.Williams ex Mast. in Gard. Chron. n.s. 14: 40, f. 9. 1880 Nepenthes ×williamsii Hort.Williams ex Mast. in Gard. Chron. n.s. 14: 40, f. 9. 1880Taxon for this nameNepenthes ×williamsii Hort.Williams ex Mast. in Gard. Chron. n.s. 14: 40, f. 9. 1880