SPECIAL ANATOMY. 135 



tlie wliole lengtli of tlie lateral part of the main portion of 

 the hyoid bone, and radiate from this toward the under 

 surface of the mucous membrane of the base of the tongue. 

 Under this muscle, and so closely blended with it as to be 

 distinguished only by the direction of its fibres which run 

 in a parallel direction forwards, is 



Hyoglossus parvus, arising from the junction of the long 

 and short cornua of the hyoid bone, and blending with hyo- 

 glossi magnus and brevis in the substance of the tongue. 

 To the posterior margin of the short cornua and of the 

 inferior extremity of the long cornu the 



Hyoideus parvus is attached, and runs obliquely down- 

 wards and backwards to the superior margin of the heel 

 process. 



The long cornu (of which there is one on each side) runs 

 obliquely upwards and backwards from the superior extre- 

 mity of the short cornu. It presents three angles, three 

 borders, and two surfaces. It assumes the form of an ex- 

 tremely acute angled isosceles triangle, with its apex down- 

 wards and forwards. The inferior angle is connected by 

 fibro-cartilage with the short cornu, the antero- superior 

 angle is connected by fibro-cartilage with the hyoid process 

 of the petrous temporal bone. From the postero-superior 

 angle, which is somewhat tuberous, the hyoideus magnus 

 and digastricus (sometimes) arise. 



Hyoideus magnus becomes inserted into the supero- 

 lateral part of the body of os hyoides by a small tendon, 

 the fibres of which separate, the foramen thus formed 

 being lubricated with synovia for the passage of the 

 tendon of 



Digastricus, which commences generally from the styloid 

 process of the occiput, being blended with the origin of 

 stylo-maxillaris, forms a f asiform belly, and then a thin 

 round tendon which plays through that of hyoideus magnus, 

 and terminates in the second muscular portion which runs 

 forwards, becoming inserted into the inferior margin of the 

 lower jaw as far forward as the symphysis. The concavity 

 of this muscle therefore is anteriorly situated. The 

 anterior margin of the long cornu presents a deep curve 

 superiorly, where the mucous membrane of the guttural 

 230uch is reflected from the internal surface to the external 

 surface of the bone. To the lower part of the internal sur- 

 face^ however, hyo-pharyngeus becomes attached, and from 



