lo6 OUTLI^vES OF EQUINE ANATOMY. 



a ridge running across the lower part of the external sur- 

 face^ a long fusiform muscle — 



Hyoglossus longus — runs forwards along the lateral part 

 of the tongue, immediately beneath the mucous mem- 

 brane. 



The superior margin is the shortest, and affords attach- 

 ment to 



Stylo -hyoideus, which arises from the styloid process of 

 the occiput, and becomes inserted into the superior margin, 

 and external surface of the extreme upper part of the long 

 cornu. 



.The posterior margin is almost straight, between it and 

 hyoideus magnus the external carotid artery passes 

 superiorly ; and lower down the twelfth or lingual nerve, 

 and the submaxillary artery, which on gaining the external 

 surface of the long cornu gives off the 



Lingual artery, which runs in a forward direction over 

 the external surface of the short cornu, through mylo- 

 hyoideus, the fibres of which separate for its passage, and 

 breaks up to form the ranine and sublingual branches. 

 The ranine runs to the tip of the tongue between the 

 genio-hyoglossus and genio-hyoideus muscles, taking a 

 wavy course, whereby it is capable of adapting itself to 

 temporary elongation of the tongue. It sends branches 

 downwards to anastomose with the superior branches of 

 the sublingual, which, after supplying the gland of the 

 same name, expends itself in the muscular structure of this 

 neighbourhood. The veins of the tongue correspond to 

 the arteries, and empty themselves into the submaxillary 

 vein. The nerves are the gustatory branch of the inferior 

 maxillary division of the fifth, and the anterior branch of the 

 glosso- pharyngeal {ninth), ivhich endoiv it with common sensa- 

 tion, and with the special sense of taste. It owes its motor 

 potver to the twelfth, lingual, or hypoglossal nerve, which 

 arises from the lateral part of the medulla oblongata, 

 and emerges from the cranium, through foramen condyloi- 

 deum. It passes over the guttural pouch, and runs in an 

 anterior direction between the pneumogastric and spinal 

 accessory nerves, over the internal and external carotid 

 arteries, and between hyoideus magnus and the long cornu 

 to the lateral part of the tongue. 



By division of the amphiarthrotic joint of the hyoid 

 long cornu with the petrous temporal bone, and bending 



