THE TONGUE. 



9 



wards. For whilst, previously, the genio-glossi were broken 

 up into transverse lamella, by the bands of the transversus, 



Fig. 169. 



they are now separated longitudinally by the interposition of 

 the bundles of the superior longitudinal muscle of the tongue, 

 between their fibres. These perpendicular longitudinal lamella 

 are very distinct in the two anterior thirds of the tongue, less 

 so in the vicinity of the papilla circumvallala, where, especially 

 in the middle of the tongue, the genio-glossus passes, in more 

 isolated bundles, to the mucous membrane ; in the root of the 

 tongue, finally, they cannot be demonstrated at all. The genio- 

 glossus ends upon the upper surface of the tongue, in such a 

 manner, that its primitive bundles, immediately beneath the 

 mucous membrane, are continuous, in groups, with little tendi- 

 nous streaks of connective tissue, which then partly become lost 

 in the deeper, very firm layer of the mucous membrane, to be 

 described presently, and partly run as far as the bases of the 

 papilla. At the root of the tongue, the genio-glossus does not 

 reach so far as the mucous membrane, which may here be easily 

 dissected away, with its mucous sacs, from the more deeply 



Fig. 169. Longitudinal section of the human tongue, nat. size ; the outlines after 

 Arnold Icon. org. (sens. ) ; g.h, genio-hyoideus ; h, hyoid bone ; g, genio-glossus ; 

 g', glosso-epiglotticus ; tr, transversus lingua ; l.s, longitudinalis superior; e, epi- 

 glottis ; m, maxilla inferior ; d, incisor tooth ; o, orbicularis oris ; l.m, levator menti; 

 I, glandulce labiates ; f,folliculi linguales ; gl, glandules linguales cum ductibus. 



