THE LINGUAL REGION 



393 



from the body are directed upward and backward, overlapping those arising 

 from the greater cornu, which are directed. upward and forward. 



Relations. By its superficial surface, with the Digastric, the Stylohyoid, Styloglossus, and 

 Mylohyoid muscles, the submaxillary ganglion, the lingual and hypoglossal nerves, the sub- 

 maxillary ducf, the ranine vein, the sublingual gland, and the deep portion of the submaxillary 

 gland. By its deep surface, with the Stylohyoid ligament, the Geniohyoglossus, Lingualis, and 

 Middle constrictor, the lingual vessels, and the glossopharyngeal nerve. 



The Chondroglossus (m. chondroglossus) is a distinct muscular slip, though it is 

 sometimes described as a part of the Hyoglossus, from which, however, it is sepa- 

 rated by the fibres of the Geniohyoglossus, which pass to the side of the pharynx. 

 It is about three-quarters to an inch in length; it arises from the inner side and 

 base of the lesser cornu and contiguous portion of the body of the hyoid bone, 

 and passes directly upward to blend with the Intrinsic muscle fibres of the tongue, 

 between the Hyoglossus and Geniohyoglossus. 



The Styloglossus (m. Styloglossus}, the shortest and smallest of the three styloid 

 muscles, arises from the anterior and outer side of the styloid process, near the 

 apex, and from the stylomandibular ligament, to which its fibres, in most cases, 



are attached by a thin aponeurosis. Passing 

 downward and forward between the internal 

 and external carotid arteries, and becoming 

 nearly horizontal in its direction, this muscle 

 divides upon the side of the tongue into two 

 portions one longitudinal, which enters the 



CUT EDGE OF SUPERIOR LINGUALIS. 



FIG. 304. Muscles on the dorsum of 

 the tongue. 



FIG. 305. Coronal section of tongue. Showing intrinsic 

 muscles, a. Lingual artery, b. Inferior lingualis, cut through, c. 

 Fibres of Hyoglossus. d. Oblique fibres of Styloglossus. e. Inser- 

 tion of Transverse lingualis. /. Superior lingualis. g. Papillae of 

 tongue, h. Vertical fibres of Geniohyglossus intersecting Trans- 

 verse lingualis. i. Septum. (Altered from Krause.) 



side of the tongue near its dorsal surface and blends with the fibres of the 

 Lingualis in front of the Hyoglossus; the other oblique, which overlaps the 

 Hyoglossus muscle and decussates with its fibres. 



Relations. By its superficial surface, from above downward, with the parotid gland, the 

 Internal pterygoid muscle, the lingual nerve, and the mucous membrane of the mouth; by its 

 deep surface, with the tonsil, the Superior constrictor, and the Hyoglossus muscle. 



Nerves. The muscles of this group are supplied by the hypoglossal nerve. 



