778 SPECIAL HISTOLOGY. 



Literature. E. Huschke, in "Fror. Not.," 1832, No. 707; "Iris," 

 1833, No. 18, 34 ; K. Steifensand, " Untersuchungen iiber die Ampullen 

 des Gehororgans," in Miiller's " Archiv," 1835; S. Pappenheim, "Die 

 specielle Gewebelehre des Gehororgans," Breslau, 1840, and Froriep's 

 "Not.," 1838, Nos. 141, 194, and 195 ; G. Breschet, " Recherches sur 

 1'organe de 1'ouie dans l'homme et les animaux verte'bre's," 2d ed. Paris, 

 1840 ; E. Krieger, " De otolithis," Berol. 1840 ; Wharton Jones, " The 

 Organ of Hearing," in Todd's " Cyclopaedia," Vol. II. p. 529; J. Hyrtl, 

 " Ueber das innere Gehororgan des Menschen und der Saugethiere," 

 Prag., 1845 ; A. Corti, " Recherches sur 1'organe de 1'ouie des mam- 

 miferes," in Zeitsch., f. wiss. Zool. III., p. 109 ; Reissner, " De auris 

 internee formatione," Dorpat, 1851; E. Harless, Art. "Horen," in 

 Wagner's "Handw. der Physiol." IV., p. 311, and " Miinchn. Gel. An- 

 zeiger," 1851, No. 31 and 37; Stannius, "Ueber die ganglibse Natur 

 des Nervus acusticus," in Gott. Nachr., 1850, No. 16 ; Ib., 1851, No. 

 17 ; [A. Kolliker, " Ueber die letzten Endigungen des Nervus Cochleae 

 und die Function der Schnecke," Wurzburg, 1854. DaC.] Besides 

 which should be consulted the general works of Krause, Huschke, Ar- 

 nold, Todd and Bowman, Reraak (Entwicklungsgeschichte), and the 

 " Icones org. sensuum," of Arnold. 



III.OF THE OLFACTORY ORGAN. 



236. The olfactory organ consists of the two nasal cavities, or fossce, 

 supported by bones and cartilages, and lined by a mucous membrane, 

 and of a certain number of- accessory cavities, viz., the frontal, sphe- 

 noidal, and ethmoidal sinuses and the antrum HigJimori. Of all these 

 cavities, however, only the uppermost portions of the nasal fossae, where 

 the olfactory nerve is distributed, are subservient to the sense of smell 

 itself, the others being either simple conducting canals, and participating 

 as well in the action of respiration, or at any rate having no direct rela- 

 tion to the olfactory sense. 



The hard structures, just named, present nothing much worthy of 

 remark ; and of the bones it need merely be mentioned, that the thin- 

 nest parts of the ethmoid consist only of a fundamental substance and 

 bone-fibres, without any Haversian canals. The nasal cartilages are 

 true cartilages, and most nearly approach those of the larynx, except 

 that the contents of the cartilage-cells are usually very pale, and with- 

 out fat, the cell-walls little thickened, and the matrix finely granular. 

 Beneath the pericJiondrium there is, also in this situation, a layer of flat- 

 tened cells, which, on the septum attains a thickness of 0-024 of a line, 

 whilst in the interior the cells are more rounded, larger, and disposed in 

 rows, in the direction of the thickness of the septum. 



With respect to the coverings of these parts, the integument of the 

 nose may be first noticed: it is characterized by a thin epidermis 



