THE ANATOMY OF THE ADULT HUMAN SALIVARY GLANDS I 7 



specialized gland of the intermediate alveolingual area, between the 

 medial line of the submaxillary duct and the lateral alveolingual group 

 of separate individual lesser subhngual glands, at the expense of the 

 volume and extent of the latter. 



In this case the median of the two intermediate glands might either 

 join the submaxillary duct or open independently on the parafrenular 

 papilla, confonning to the two known types of the greater sublingual 

 or Bartholinian gland, while the lateral gland would appear as an 

 entirely new component of the alveolingual complex, evolved by com- 

 bining certain of the medial anlages of the lesser subhngual group 

 into a separate and distinct gland with its own conducting canal. 

 This condition is purely hypothetical and has not yet been observed 

 in the mammalian forms e.xamined. The nearest approach to it is 

 offered, as above stated, by the apparent reduplication of the greater 

 sublingual gland seen in Hydrochoerus. 



3. Tic Lesser Sublingual, Fst/imian, and Palatine Glands. — The 

 lateral component of the adult human alveolingual field is formed by a 

 mass of separate individual glands, each with its own ductule, opening 

 upon the lateral alveolingual ridge of the oral mucosa. The cephalic 

 elements of this chain of separate individual glands are always more 

 numerous and better developed than the caudal members of the 

 series, and they constitute the mass of the lesser sublingual or Rivinian 

 glands proper. In general they lie lateral to the submaxillary duct 

 and to its accessory or secondary tributaries, and also lateral to the 

 greater sublingual or Bartholinian gland and duct, when this member 

 of the alveolingual complex develops. Occasionally a few scattered 

 glandular masses extend mesad beneath the greater sublingual and 

 submaxillary ducts to the lateral border of the tongue. These ele- 

 ments may be responsible for the development of the Blandin-Nuhn 

 gland in the apical portion of the tongue (Fig. i8) and for the occasional 

 glandular masses which, under the name of Weber's gland, are de- 

 scribed as occupying portions of the interval between the submaxillary 

 duct and the lateral surface of the tongue proper. 



The caudal end of the group of the lesser sublingual glands usually 

 tails ofi into a narrow dorsally deflected process which extends nearly 

 to the Ungual nerve. In some cases the ribbon of the lesser sublingual 

 glands is prolonged mesad of the nerve into the anterior faucial pillar. 



