The other day I have been struck by the following phrase in a paper by Dr. G. Brandes, entitled: »Ueber die Nasenaffen”, Zeitschrift für Naturwissenschaften, 1901, p. 284: »Es ist wohl zweifellos, dass der tibetanische und der »bornesische Nasenaffe zu einer Gattung zu vereinigen sind, »als deren wesentliche Charactere die mächtige Entwick»lung der Nasenmuskulatur und die schwach ausgebildeten »oder gar ganz fehlenden Nasenbeine zu gelten haben. Ich »werde danach von Rhinopithecus nasicus (Borneo) und roxellanae (Tibet) sprechen”. For reasons hereafter to explain the named monkeys cannot be united under the same generic title. We however will admit for a moment »they can”, than may be asked why Dr. Brandes did not accept the generic name » Nasalis having a priority of about sixty years over » Rhinopithecus”! Further may be asked why he excluded another Rhinopithecus, Rh. Bieti? The latter has been described and perfectly figured by A. Milne Edwards in »Bulletin du Museum d’Histoire naturelle, 1897” and »Nouvelles Archives du Museum d’Histoire naturelle, 1898”, as une nouvelle espèce du genre Rhinopithecus”, known as the »Singe des neiges” ou » Tchru tchra” by the inhabitants; it has been procured on tbe »versant occidental de la chaine séparant la vallée du Mékong de celle du fleuve Bleu dans les forêts”; it has a nose exactly like Roxellana 1) and like that species very short nasal bones. It seems that Rh. Bieti was an unknown species to Dr. Brandes. Further, the name nasicus is not correct, as another specific title larvatus was bestowed upon the Borneo-animal twenty years before, by its first describer; therefore the correct orthography should be: Nasalis larvatus from Borneo, Nasalis Roxellana from the continent and Nasalis Bieti too from the continent, if Dr. Brandes’ hypothesis could be accepted. The three species however cannot by any means be united in one genus, as the Bornean Proboscis-monkey differs from all other Semnopitheci by its having nasal bones much longer than in any other Semnopithecus! In the youngest skull of our Proboscis-monkeyseries the nasalia are a good deal longer than in the figures of the skulls of very old specimens of Roxellana and Bieti, figured in Milne Edwards’ papers; in the Bornean-species therefore the »Nasenbeine” are the inverse of »schwach ausgebildet”, as Dr. Brandes exhibited as base of his hypothesis; so that till now the Bornean-Monkey stands alone in the genus Nasalis, meanwhile the other two are to be united under the generic title Rhinopithecus.