444 SPECIAL HISTOLOGY. 



reached the lower surface of the margin of the tongue, into a great 

 number of thin transverse lamella?, which, more or less curved, pene- 

 trate superiorly between the lamellae of the transverse muscle and in 

 their further course, present exactly the same relations as those of the 

 genio-glossus, to which they are applied externally, except, that as their 

 fibres ascend towards the dorsum of the tongue, they take a slightly 

 oblique direction inwards. Upon the dorsum of the tongue, the Jiyo- 

 glossus lies between the genio-glossus and the upper edge of the trans- 

 versus; it presents, like the former, longitudinal plates, with perpendi- 

 cular fibres, between which the upper longitudinal fibres lie, and it 

 finally, also, terminates in the mucous membrane. The expansion of 

 the Jiyo-glossus is most distinct and strongest, in the middle of the 

 tongue, where the chief mass of the baseo-glossus lies ; it is only behind 

 that it becomes more indistinct, the lamellae of the cerato-glossus being 

 here very delicate, and lying more horizontally ; however, they still pene- 

 trate between those of the transversus and terminate upon the dorsum 

 of the tongue. 



The stylo-glossus (Fig. 170, st. gl.}, in general, divides into two 

 bundles, which have totally different relations ; the posterior, smaller 

 one, passes between the cerato-glossus and baseo-glossus, and between 

 the fasciculi of the latter, directly inwards, penetrating, in a few 

 bundles, between the lamella? of the lingualis and genio-glossus, as far 

 as the septum linguce, where it becomes attached, in common with the 

 somewhat superior fibres of the transverse muscle. The principal mass 

 of the stylo-glossus passes inwards and downwards at the margin of the 

 tongue, unites in front of the Jiyo-glossus with the lingualis inferior, and 

 terminates in the mucous membrane of the lower surface of the apex of 

 the tongue and of the point itself; the anterior bundles of the two 

 muscles becoming united in an arch. 



The lingualis of authors, which I shall call lingualis or longitudinalis 

 inferior (Fig. 170, 1. i), is a tolerably strong, longitudinal bundle of 

 muscular fibres placed upon the lower surface of the tongue, between 

 the genio-glossus and hyo-glossus, but whose commencement and termi- 

 nation are not readily discoverable. The posterior portion of the lin- 

 gualis inferior appears at first to become lost in numerous superimposed 

 flat bundles between the transverse fibres of the genio-glossus (glosso- 

 pliaryngeus), of the stylo-glossus, and of the transversus, at the root of 

 the tongue ; more carefully traced, however, it is found that these, like 

 the posterior portions of the genio-glossus, break up into many lamellce, 

 which ascend, slightly curved, between the transverse fibres, as far as 

 the outer portions of the glandular layer of the root of the tongue ; and 

 finally, like the plates of the genio-glossus, which lie internal to them, 

 end in it. Anteriorly the lingualis inferior unites with the larger 

 bundles of the stylo-glossus ; ending at the point of the tongue with 



