當發現婆羅洲並不存在血紅豬籠草後，學者們就意識到弗雷德里克·威廉·伯比奇的雜種假說是完全錯誤的。[11]1884年，愛德華·奧古斯特·馮里格爾在《Gartenflora》中發表了一篇關於諾斯豬籠草的短文。[12]1895年，君特·貝克·馮·曼那哥塔-勒馳奈在其1895年的專著《豬籠草屬》中描述了將一種豬籠草命名為偽豬籠草（N. spuria）。[2]該名稱為不合法名，現在被認為是諾斯豬籠草的同物異名。[5]雅各布·海斯伯特·博爾拉吉（Jacob Gijsbert Boerlage）在其1900年的著作《荷屬東印度群島植物指南》（Handleiding tot de kennis der flora van Nederlandsch Indië）中將諾斯豬籠草的學名「N. northiana」錯印為「N. nordtiana」。 [13]其為印刷錯誤。[5]
1909年，R·傑瑞-迪斯洛吉斯（R. Jarry-Desloges）描述了諾斯豬籠草的一個變種——美麗諾斯豬籠草（Nepenthes northiana var. pulchra）。[5][15]其顏色鮮艷，捕蟲籠為紫紅色，唇有更醒目的紅黃條紋。相比之下，原變種的捕蟲籠多為黃色，並帶有棕色或紅色的斑點。[14]但美麗諾斯豬籠草現已不被認為是有效的分類。[16]
Mr E. [Everett] went up a mountain near and brought me down some grand trailing specimens of the largest of all pitcher-plants, which I festooned round the balcony by its yards of trailing stems. I painted a portrait of the largest, and my picture afterwards induced Mr Veitch to send a traveller to seek the seeds, from which he raised plants and Sir Joseph Hooker named the species Nepenthes northiana. These pitchers are often over a foot long, and richly covered with crimson blotches.
"The specimen from which Miss North's drawing was made was procured by Mr. Herbert Everett of the Borneo Company who "traversed pathless forests amid snakes and leeches to find and bring it down to the artist." "Only those", writes Miss North, "who have been in such places can understand the difficulties of progress there. The specimens grew on the branches of a tree about 1000 feet above the sea on the limestone mountains of Sarawak. When I received them I tied them in festoons all round the verandah and grumbled at having only one small half-sheet of paper left to paint them on.""
"Your figure of Nepenthes Northiana was very good. Miss North's drawing, however, has, if I recollect right, a ground-tint of bright reddish-crimson on which darker blotches are laid. It is a fine thing, and, as I firmly believe, a natural hybrid between N. sanguinea × N. Veitchii. The oblique mouth of the urns would suggest N. Rajah as one of the parents, but then his highness only holds court, so far as we know at present, on Kina Balu, 250 miles further north, and never at a less altitude than 4500 feet, rising to near 10,000 feet.
In earlier times he may have been an inhabitant of the plains—at any rate no one can place the pitchers of N. Northiana, N. Veitchii, and N. sanguinea side by side without being struck by their affinity. Again, a glance at your engraving of N. Northiana reminds one of a long-urned form of N. Rajah in obliquity of mouth and its wavy-margined frill. The cauline pitchers of N. Rajah have never yet been figuted. I was with Mr. Harry Veitch when Miss North first showed him the picture of N. Northiana, and it was a revelation to us both. I had the latitude and longitude of its habitat in my portfolio when I left Chelsea for Borneo, but unfortunately never had the chance of seeing Sarawak ; my lot was the wild north-west coast, among the pirate chiefs, and very good genial fellows I found them !"
Folia mediocria petiolata, lanceolata, nervis longitudinalibus utrinque 5-6, vagina in alas 2 basi peltatas decurrente ; ascidia rosularum et inferiora ignota ; ascidia superiora magna, tubulosa v. infundibuliformia ; parte inferiore costis 2 prominentibus, os versus alis 2 fimbriatis ; peristomio expanso, 25-60 mm lato, costis c. 1 mm distantibus, dentibus vix longioribus quam latis ; operculo ovato, facie inferiore plana v. prope basin obtuse carinata ; inflorescentia racemus longus pedicellis longis fere omnibus 2-floris ; indumentum in caulibus foliisque fere 0, in ascidiis adpressum parcum in inflorescentiis tenue densum ferrugineum.
"I have seen type material of this species [N. decurrens] in the Herbarium of the Sarawak Museum: 2 pitcher-bearing leaves, torn from the stem in such a way, that the manner, in which they are inserted on it, is no longer visible.
The pitchers show a great resemblance with those of the drawing of N. Northiana in The Gardeners' Chronicle, 1881, 2, between p. 724 and 725. This drawing shows 2 keels on the lid and wings over the whole pitchers, even over the curved part, but these are insignificant differences. According to the descriptions, the stems of N. Northiana are less thick than those of N. decurrens, and the leaves are sessile, but this too is not so important a difference as it seems. The most important difference is in the inflorescences. N. Northiana has a loose-flowered triangular raceme, with 2 to 3 mm long pedicels, N. decurrens has a long and coarse raceme, with long pedicels (the description of both inflorescences is very imperfect). Therefore it is impossible for me to determine the 3 above mentioned inferior pitchers, I found in the Sarawak Herbarium, and collected by Everett in 1892. This Mr. Everett may be the same which collected N. Northiana for Marianne North and therefore it seems possible that the 3 pitchers mentioned are the basal ones of the latter species. They are ovate-ellipsoidal, resp. 23, 24 and 26 cm high, 10, 11 and 10 cm wide, widest about, or somewhat below the middle ; the peristomes are as in N. decurrens, resp. 3, 4 and 2 1/2 cm broad, the mouth is very oblique, occupying about half the height of the pitcher, the lid has one median keel, but is crumpled, and the form, though not well visible, seems to be that of N. decurrens."
Macfarlane, J.M. 1925. A new species of Nepenthes from Borneo (Nepenthes decurrens). Bulletin of Miscellaneous Information (Royal Gardens, Kew): 35–37.
Bauer, U., C.J. Clemente, T. Renner & W. Federle 2012. Form follows function: morphological diversification and alternative trapping strategies in carnivorous Nepenthes pitcher plants. Journal of Evolutionary Biology25(1): 90–102. doi:10.1111/j.1420-9101.2011.02406.x
Turnbull, J.R. & A.T. Middleton 1981. A preliminary review of the Sabah species of Nepenthes, including a regional list and some selected localities. Unpublished mimeograph report to the Sabah Parks Trustees.
Lee, C.C. 2004. Nepenthes. In: Sarawak Bau Limestone Biodiversity. H.S. Yong, F.S.P. Ng and E.E.L. Yen (eds). The Sarawak Museum Journal Vol. LIX, No. 80; Special Issue No. 6: 71–77.
Meimberg, H., A. Wistuba, P. Dittrich & G. Heubl 2001. Molecular phylogeny of Nepenthaceae based on cladistic analysis of plastid trnK intron sequence data. Plant Biology3(2): 164–175. doi:10.1055/s-2001-12897
Meimberg, H. & G. Heubl 2006. Introduction of a nuclear marker for phylogenetic analysis of Nepenthaceae. Plant Biology8(6): 831–840. doi:10.1055/s-2006-924676
Meimberg, H., S. Thalhammer, A. Brachmann & G. Heubl 2006. Comparative analysis of a translocated copy of the trnK intron in carnivorous family Nepenthaceae. Molecular Phylogenetics and Evolution39(2): 478–490. doi:10.1016/j.ympev.2005.11.023
Renner, T. & C.D. Specht 2011. A sticky situation: assessing adaptations for plant carnivory in the Caryophyllales by means of stochastic character mapping. International Journal of Plant Sciences172(7): 889–901. doi:10.1086/660882
