 A number of early sources disagree, however, noting that the plant referred to as "nilad" is the Indigo plant ("Indigoferra tinctoria"), a different plant altogether.Emma Helen Blair, in the multi-volume collection of Philippine documents The Philippine Islands, notes "The name Manila is derived from a Tagal word," ' Manilad "', meaning 'a place overgrown with Nilad' which is the name of a small tree, bearing white flowers.Julio Nakpil asserted that the dropping of the "d" at the end of the name was probably a mistake on the part of the Spaniards