Danser recognised 65 species in total, of which 52 were given detailed treatments. This number included 17 newly described taxa: "N. carunculata" (later synonymised with "N. bongso"), "N. clipeata", "N. dubia", "N. ephippiata", "N. fusca", "N. inermis", "N. insignis", "N. leptochila" (later synonymised with "N. hirsuta"), "N. mollis", "N. paniculata", "N. papuana", "N. pectinata" (later synonymised with "N. gymnamphora"), "N. petiolata", "N. pilosa", "N. spectabilis", "N. tobaica", and "N. tomoriana". All were described in great detail, with many accompanied by line drawings. Danser synonymised "N. edwardsiana" with "N. villosa", "N. hemsleyana" with "N. rafflesiana", and "N. ramispina" with "N. gracillima"; all three were later reinstated as valid species.