COMPARATIVE ANATOMY OF THE MAMMALIAN ORGAN OF JACOBSON. 255 



Turner, AY., " The Dumb-bell shaped Bone in the palate of Ornithorhynchus compared with the Prenasal Bone 

 of the Pig," Journ. of Anat. and Phys., vol. xix., p. 214, 1885. 



Wiedersheim, R., " Die Stammesentwickelung des Jacobson'schen Organes," Tagbl. Versamml. deutscher 

 Naturforsch v. Aertze in Salzburg, 1881. 



Wiedersheim, R., " Die Anatomie der Gymnophionen," 1879. 



Wilson, J. T., " Observation upon the Anatomy and Relations of the Dumb-bell shaped bone in Ornitho- 

 rhynchus, etc.," Proc. Linn. Soc. F.S.W., 1897. 



Wilson, J. T., and Martin, C. J., " Observations upon the Anatomy of the Muzzle of the Ornithorhynchus," 

 Macleay Mem. Vol., Linn. Soc. N.S.W., 1893. 



Wright, R. R., "On the Organ of Jacobson in Ophidia," Zool. Anz., No. 144, 1883. 



Zuckerkandl, E., Das periphere Geruchsorgan der Saugethiere, eine Vergleichend. Anat. Studie, 

 Stuttgart. 



REFERENCES TO PLATES. 



General. — a. J.c, anterior process of Jacobson's cartilage; a.n.f.c, anterior process of the nasal floor 

 cartilage; g., glands; i.t., inferior turbinal bone ; J.c, Jacobson's cartilage; J.c?., Jacobson's duct; J.o., 

 Jacobson's organ; Id., lachrymal duct; mx., maxillary bone; n.f.b., nasal floor bone; n./.c, nasal floor 

 cartilage; n.p.c, naso-palatine canal; n.s., nasal septum; o.b.J.c, outer bar of Jacobson's cartilage; o.n.f.c, 

 outer part of the nasal floor cartilage ; p.c, papillary cartilage ; p.n., prenasal cartilage ; Pmx., premaxillary 

 bone; p.Pmx., palatine process of the premaxillary; Pvo., pre vomer; rud.t., rudimentary turbinal cartilage; 

 u.c.c, united canal cartilages ; i.e., anterior processes of Jacobson's cartilage and of the outer nasal floor 

 cartilage; t.p., turbinal plate; v., blood-vessel; vol., nasal valve; vo., vomer; v.s., vascular space. 



The parts shaded in lines are bones ; whilst the dotted structures are cartilages. 



Plate I. 



Fig. 1-3. Transverse sections of the organ of Jacobson in Ornithorhynchus anatinus, x 5. 

 Fig. 4-7. „ ,, „ Echidna aculeata, x 20. 



Fig. 8-11. ,, „ ,, Dasyurus viverrinus (mammary foetal speci- 



men), x 20. 

 Fig. 12-15. ,, ,, „ Petaurus breviceps, x 20. 



Fig. 16-18. „ ,, „ Dasypus villosus, x 5. 



Plate II. 



Fig. 19-22. Transverse sections of the organ of Jacobson in Miniopterus schreibersii, x 25. 

 Fig. 23-24. ,, „ „ Erinaceus europosus, x 10. 



Fig. 25-27. 

 Fig. 28-30. 

 Fig. 31-32. 

 Fig. 33-35. 

 Fig. 36-38. 



Felis domestica (Young), x 10. 

 Sus scrofa (foetal), x 20. 

 Equus caballus (foetal), x 7. 

 Bos taurus (foetal), x 10. 

 Lepus cuniculus (foetal), x 20. 



Fig. 39 Transverse section of snout of Delphinaptera leucas (foetal), x \\ 



VOL. XXXIX. PART I. (NO. 8). 



6 AUG. 1898 



2 Q 



