66 



THE MUSCLES. 



pli 



Fig. 6i. 



23, 24, 25. Mm. petroJii/oidei posteriores (Ecker), (Fig's. 6i 



' 3. 4)- 



Cuvier, »nn. sfylohyoidei, I.e., p. 537. — Dugès, 20, 21, 22, masto-hyoi- 

 deus (Fig. 4). — Zenker, pelro-hyoideus superior and inferior. — 

 Klein, stylo-liijoideus, I. c, p. 18. 



These are three long-, thin muscles, which He nearly parallel to 

 one another, and rnn from the prootic bone to the posterior cornu 



of the hyoid bone. All three arise, 

 covered by the m. sternocleidomastoi- 

 (leus, from the lateral extremity of 

 the prootic, pass round the pharynx 

 and are attached, the w?. petrolii/oidevs 

 posterior pjvimns (Fig". 6\ pk'i) to the 

 anterior extremity, the secundus (Fig*. 

 6 1 /(A 3) to the middle ; and the terthis 

 (Fig. 61 jjJi 4) to the hinder extremity 

 of the posterior horn of the hyoid 

 bone. 



26. M. /li/ofj/ossvs (Figs. 59, 60, 

 61%). 

 Cuvier, /. c, p. 588. — Dugès, 24, hyo-glosse. 

 Arises from the bony posterior ex- 

 tremity of the hinder process of the 

 hyoid bone {lig'). The muscles of the 

 two sides pass forwards and converge 

 to the middle line, where they unite. 

 The azygos muscle thus formed runs 

 forwards on the ventral surface of the 

 hyoid bone, between the mm. gen'ioJi//oidei, over the anterior border 

 of the hyoid, and passes into the tongue, where it turns backwards 

 and runs to the tip. (For action, see tongue.) 



Muscles of the hyoid bone of liana escx- 

 . Ie7itii, seen from tlie riglit side and 

 below. 



//' Anterior cornu. 



H'' Posterior cornu. 



hfl M. hyoglossus. 



H fi Body of hyoid bone. 



ph I M. petrohyoideiis anterior. 



]ih 2, 3. 4 Mm. petrohyoidei posteriores. 



sm M. submaxiUaris. 



sm' Hinder portion of same. 



27. lif. geniorjIossn.H. 



Cuvier, I. c, p. 5S7. — Meckel, /. c, IV, 339. — Dugès, 23, genio-glosse. 



Arises above the insertion of the m. geniohyoulens on either side 

 near the middle line from the two anterior bones of the lower jaw. 

 The two origins quickly unite to form a thick, very firm muscular 

 belly, which in its course backwards rapidly thins, and is distrilnited 

 by numerous bundles ; decussating* with the fibres of the 7n. hyoglossvs 

 at an acute angle, it runs on to the anterior extremity of the tongue. 



