LINGUAL MUSCLES. 281 



smooth and pellucid infero-laterally, where the ranine vein can 

 be traced. Irregularly pyramidal in shape, it has a root or base, 

 a body, and an apex or tip. 



The base, the widest and thickest part, is muscularly attached 

 to the OS hyoides and inferior maxilla ; to the epiglottis by a fold 

 of mucous membrane, the glosso-epiglottidean ligament ; and to 

 the velum pendulum palati by the anterior pillars of the fauces. 

 The apex, or tip, is free, and broad in the horse, being directed 

 forwards against the inner surfaces of the lower incisors. The 

 under surface of the tongue is attached anteriorly to the lower 

 jaw by the genio-hyo-glossi muscles, and laterally by the reflec- 

 tion of the mucous membrane, over the sublingual glands, to 

 the innsr surface of the inferior gums. Antero-mesially, the 

 mucous membrane folds into a frcenurio linguoi, or anterior 

 pillar, in front of which is a small papilla, containing the open- 

 ings of the submaxillary glands ; and on either side, between 

 the tongue and maxilla, are the ducts of the sublingual glands. 



The dorsum, or upper surface, is convex, and marked' along 

 its middle by a raphe, or groove, which indicates the division of 

 the organ into two lateral halves. The raphe terminates near 

 the base in a cavity known as the foramen cwcum, or foramen 

 of Morgagni, in which numerous mucous follicles open. 



Posteriorly the tongue is divided by fibrous tissue, which forms 

 a partial longitudinal septem, commencing near the hyoid bone, 

 and losing itself in the muscles. According to Briihl, a piece of 

 fibro-cartilage exists here, peculiar to the solipede, and it has 

 been named the lingual cartilage. 



LINGUAL MUSCLES. 



The substance of the tongue is composed chiefly of muscular 

 layers running in different directions, between which adipose 

 tissue is interposed. The muscles are divided into extrinsic and 

 intrinsic. 



The extrinsic muscles of the tonoue are as follows : — 



Hyo-glossus longus. 

 Hyo-glossus brevis. 

 Hyo-glossus parvus. 



Genio-hyo-glossus. 

 Pharyngo-glossus. 

 Palato-2;] 



