MAMMALIAN ALVEOLINGUAL SALIVARY AREA 337 



ganglion. The aniage is solid throughout and subsequently acquires 

 a lumen. The lesser sublinguals of the pig he found in an embryo of 

 5 centimeters as short, unbranched plugs in a row lateral to the 

 ducts of the larger glands. They arise from the surface of the alveo- 

 lingual region, not from furrows, and are not associated with an epi- 

 thehal crest. His figure of their condition in a 7 centimeter pig is 

 well known and often reproduced. They are shown lateral to the 

 ducts of the submaxillary and greater subhngual glands, which extend 

 horizontally in contact, the subma.xillary being ventral, while the 

 lesser ducts are directed vertically and attached to the oral epithehum 

 dorsal to the larger ones. In man their history diiifers somewhat. 

 In an embryo of 10 weeks they arise from a lateral furrow of the al- 

 veoHngual gutter, from the fundus of which a solid epithelial keel 

 projects ventrad. To this are attached a few short, rounded sprouts. 

 He also notes the presence of two other sprouts which he assigns to 

 this series, one from the lingual sulcus, one from the phca sublingualis. 

 In an embryo of 12 weeks 11-13 sprouts in a row were present on 

 each side, the first close to the lateral side of the orifice of the sub- 

 ma.xillary. They now arise from the lateral surface of the plica sub- 

 linguahs. The sublinguaUs major in the pig arises, in the youngest 

 embryo described, as a crest from the side of that of the submaxillary. 

 Distad the crest is continued as a free-growing sprout, proximad it 

 advances, and, separating by constriction, produces the horizontal por- 

 tion of the duct. In man it has a similar history. From the account 

 of its development in these two forms the sublingualis major would 

 appear to be a lateral derivative of the submaxillary, but not a simple 

 branch, for its advance is provided by a keel, and in the adult it may 

 have a separate orifice. 



The findings in a 9 milhmeter embryo of a mouse tend to cast doubt 

 upon so simple a solution of the problem of the subungualis major. 



Die Subma.xiUaris ging aus der Furche zur Zeite der Zunge ziemlich weit hinten 

 ab; das hintere Ende hatte schon kleine Knospen abgegeben; in dem vorderen 

 Thfile des .'\iisfiilirungsgangcs ist ein Lumen entstanden, welches auf der rechten 

 Seite mit der Mundhohle communicirt, wahrend es linkerseits noch abgeschlossen 

 ist. Die Sublingualis ist durchweg massiv. Wahrend wir sie aber bei den fruher 

 beschriebenen Formen von der Subma.xillarisanlage ausgehend sahen, geht sie bei 

 der Maus selbststiindig von dem Mundboden aus und zwar von der Bodentlache 

 des Sulcus alveololingualis — nicht von den diese Flache seitlich begrenzenden 



