BLOOD-VESSELS OF THE TONGUE. 467 



tongue, to terminate in little flattened sacs divided into several 



cells, and having sometimes, a diameter of three lines. 



From all these follicles, comes that profusion of muoous 



secretion, which we see covering the tongue in diseases. 



He describes the sebaceous glands of the skin as being 



analogous in structure to these follicles, as well as those of the 



trachea and of the inside of the lips and cheeks. 



Soemmering has lately published some elegant engraved 

 copies of drawings of these papillae, when they were magnified 

 twenty-five times ; from which it appears that a very large 

 number of vessels, particularly of arteries, exist in them. 

 These vessels are arranged in a serpentine direction, and are 

 prominent on the surface ; but they appear doubled, and the 

 most prominent part is the doubled end. This arrangement 

 of vessels is perceptible on the sides of the tongue, as well as 

 on the papillae. 



Behind the large papillae is a foramen, first described by 

 Morgagni, and called by him Foramen Cwcum. It is the 

 orifice of a cavity which is not deep ; the excretory ducts of 

 several mucous glands open into it. 



On the upper surface of the tongue, a groove is often to be 

 seen, which is called the linea mediana, and divides it into two 

 equal lateral parts.* Below, the lining membrane of the mouth, 

 as it is continued from the lower jaw to the tongue, forms a 

 plait, which acts as a ligament, and is called the frcenum lingua. 

 It is attached to the middle of the tongue, % at some distance 

 behind the apex. t 



The tongue is well supplied with blood-vessels, which are 

 derived Irom the lingual branch of the external carotid on 

 each side. This artery passes from the external carotid, 

 upwards, inwards, and forwards, to the body of the tongue. 

 In this course it sends off several small arteries to the contig- 

 uous parts, and one which is spent about the epiglottis and the 

 adjoining parts, called the Dorsalis Lingua. About the 

 anterior edge of the hyo-glossus muscle, it divides into two 



* This groove indicates the position of the middle raphe of Gerdy. 



