181 



in man. It has escaped his atieniion ihai Rctsch. who is cited by 

 hioi a propos of the Meatus Xasopalatiiius, (I.e. p. 414. He writes : 

 Rrisce is the discoverer of the organ, and just in man in whom 

 it is normally present as was corroborated later on. 



KöLUKKR- and Hkbzfeld'; found it regularly in children while 

 it is seldom wanting tn adults. When this was the case it had 

 probably to be ascribed to former diseases of the nasal septum. 



The description of RrTSCH'), who also gives a clear representation 

 of the orifice of the organ, with a sound brought into it, on the 

 nasal septum of a child, reads as follows: '*In anteriore et inferiore 

 parte sepii juxia palatum in uiroque Uitere foramen apjiaret, sen 

 osculum cujiisdam ductus de cujus usu et existentia nil apud authores 

 legi: inservire muco excerneudo exisiimo". 



Jacobson also, not knowing RrrscH's work, is inclined to consider 

 the organ as being secretory, aiihongh the |K>werful innervation 

 pleads for a sensory function, but I.e. p. 422"^ -. -'quel agent extérieur 

 pourroit aller se (aire percevoir dans un receptacle si cache, si profond, 

 si pen acce^ibler" 



CuviER himself still thinks — under reserve — he has to accept 

 a kind of olfactory perception and the later wriiei-s do this too. It 

 is usually assumed that the organ serves to smell the food which 

 has already been taken into the mouth : in mammals the odour 

 would then rise up through the Meatus Nasoi^laiinus. This can 

 however not be the case in the lioi-se or the donkey nor in the 

 camel or giraliV, because here ihe Meatus is no longer oj>ened to 

 the buccal cavity, while their Organoii Vomei-onasale cannot be held 

 to be rudimentary as is the case in man. 



The secretory function is evident on account of the numerous 

 glands iKöi.i.iKER, I. c. p. 11) which till the ot^in with mucus, which 

 streams out through ciliary motion, but the difficulties itgainst accepting 



') A. KöLLiKER. Ueber die J.^cobsonsohen Organe des Meuschen. Reprinted 

 from the Festschrift fur RI^ECKER, Leipzig 1S77. 



-) P. Herzfkld, Ueber das Jacobsonscbe Organ des Menschen und der Sauge- 

 tbiere. Zoologische Jabrbücber, Abtb. for Anat. uudOnlogeuiederTbiere Bd. 3, 1S89. 



Herzfeld gives a summary of Ibe mammals in which the organ had been 

 found by him and others up to 1889, also in coimeclion with the meatus 

 nasopalatimis. He might have addeii that Jaoobsox bad also already observed it 

 ill the marsupials (kangaroo). Later on it was also found in the Monotreinata 

 and Eiienlata. 



>)F. RuYSOH, Thesaurus anatomicus III. Amslelodami, 1724. p. 2G. N^\ LXl. 6. 

 Illustration: Tab. IV, tig. 5. 



KóLLiKEK (1877) cited the description, mentioned above, from an edition of 

 1703 p. 49; hence more than 100 years before Cuvier's repoit. 



