THE SUBLINGUAL SPACE. 1581 



The circumvallate papillae l are imperfectly developed for some time after birth, so 

 much so that it is not easy to recognize them. The foliate papillae are also relatively 

 undeveloped. On the other hand, the fungiform papillae are proportionately both 

 larger and more numerous than in the adult. The development of the adenoid tissue 

 at the back of the tongue occurs during the last two months of foetal life. In places 

 the connective tissue surrounding the ducts of the mucous glands becomes infiltrated 

 with leucocytes and is transformed into lymphoid tissue (Stohr). 



THE SUBLINGUAL SPACE. 



This space is between the lower jaw and the tongue, above the mylo-hyoid, and 

 bounded behind by the fold of the anterior pillar of the fauces passing to the tongue. 

 It is lined with thin, smooth mucous membrane reflected from the mandible to the 

 tongue and attached lightly to the parts beneath. With the mouth closed, this 

 space is filled by the tongue. It is best examined in the living subject when the tip 

 of the tongue is against the upper incisors. A fold of mucous membrane, the frenum, 



FIG. 1342. 



Plica fimbriata 



Frenum 



ublingual ridge 

 .Orifices of submaxillary and 

 sublingual ducts 



Sublingual space, tongue pulled up. 



if well developed, passes in the middle line from the tongue to end over the floor of 

 the mouth. Close to its termination on either side is a smooth elevation caused by 

 the sublingual gland, which in the present position is drawn upward under the 

 tongue. A varying number of gland-ducts perforate the mucous membrane with 

 orifices hardly visible to the naked eye. Internal to these swellings at the lower end 

 of the frenum is a small enlargement on each side of the median line, so closely 

 blended, however, as to seem but one ; these elevations, the carimcula: salivares, 

 mark the point at which the duct of the submaxillary gland opens on each side. 

 This duct runs along the floor of the sublingual space between the mylo-hyoid 

 muscle and the mucous membrane, a small part of the gland usually accompanying 

 the duct a short distance over the muscle, forming a prominence, the sublingual 

 ridge (plica sublingualis). A constant group of glands is found in the mucous 

 membrane below the incisors. 2 



1 Stahr : Zeitschrift fiir Morph. und Anthrop., Bd. iv., Heft 2, 1902. 



2 The sublingtial bursa alleged to exist on either side of the frenum has not been described, 

 since it is at most extremely uncommon. 



