THE TEETH. 467 



acid is also frequently of service. The muscular substance of the tongue 

 must be examined by minute dissection, a method which may be car- 

 ried very far, especially in tongues which are half macerated from hav- 

 ing long lain in spirit. Recent tongues are also of use, but are by no 

 means so good, and it is usually necessary to boil them until they are 

 quite soft ; and to procure sections for the microscope the tongue may 

 be dried or hardened by boiling, or by strong alcohol. In all three 

 methods caustic soda is of great service in clearing up the tissue, 

 although it undoubtedly attacks the muscular fibres a little. Perpen- 

 dicular and longitudinal sections in various directions are to be recom- 

 mended, especially in the glandular region. With respect to the glands, 

 the most important points have been already stated. 



Literature. W. Bowman, Art. " Mucous Membrane," in Todd's 

 " Cyclopaedia of Anatomy," April, 1842; E. H. Weber, " Ueber die 

 Schleimbalge und zusammengesetzten Drh'sen der Zunge und Uber den 

 Bau der Parotis," in Meckel's " Archiv," 1827, pp. 276-280 ; A. Se- 

 bastian, " Recherches anatomiques, physiologiques et pathologiques sur 

 les glandes labiales," Groningue, 1842; Nuhn, "Ueber eine bis jetzt 

 nicht naher beschriebene Druse im Innern der Zungenspitze," Mann- 

 heim, 1845 ; N. Ward, Art. " Salivary Glands," in Todd's " Cyc. of 

 Anat.," Sept. 1848, part xxxiii. p. 421 ; C. Rahn, "Einiges Uber die 

 Speichelsecretion," Zurich, 1850; C. Ludwig, " Neue Versuche Uber 

 die Beihulfe der Nerven zur Speichelsecretion," in "Mitth. der Zurch. 

 nat. Ges.," 1850, Nos. 53 and 54, and " Zeitschr. f. rat. Med.," 1851 ; 

 C. J. Baur, " Ueber den Bau der Zunge," in Meckel's " Archiv," 

 1822, p. 350 ; P. N. Gerdy, " De la Structure de la Langue," in " Re- 

 cherches d'Anatornie, de Physiologic, et de Pathologic," Paris, 1823 ; 

 P. F. Blandin, "Sur la structure de la Langue," in the "Archiv. 

 gener. de Medecine," 1823; J. Zaglas on the "Muscular Structure of 

 the Tongue of Man and certain Mammalia," in the " Annals of Anatomy 

 and Physiology," ed. by J. Goodsir, 1850, I. p. 1 ; H. Hyde Salter, 

 Art. " Tongue," in Todd's " Cycl. of Anat.," iv. June and September, 

 1850 ; C. B. Briihl, " Ueber den Bau der Zunge der Haussaugethiere," 

 in " Kleine Beitrage zur Anatomic d. Haussaugethiere," Wien, 1850, 

 pp. 1-6; Sappey, " Ueber die Lymphgefasse der Zunge," in " Comptes 

 rendus," 1847, p. 26; and "Froriep's Notizen," 1848, vi. p. 88. 

 Besides these, compare the anatomical works of E. H. Weber, Valentin 

 (im Handw. d. Phys.), Todd and Bowman, Henle, Arnold, Huschke, 

 Krause, and myself; the figures of Berres, Arnold, and Langenbeck. 



D. OF THE TEETH. 



137. The teeth are hard organs inserted into the alveolar processes 

 of the jaws, which although to some extent identical in structure with 



