82 SALIVARY GLANDS OF LOWER PRIMATES 



then continues forward under cover of the lesser subhngual glands (j), 

 and finally appears above the cephahc margin of the latter. In this 

 part of its course the duct of the greater sublingual gland (2) , turning 

 cephalomesad, reaches and accompanies the submaxillary duct along 

 its submucous border for a short distance. Submaxillary and greater 

 sublingual ducts then unite, forming a short common terminal segment 

 (4) which opens by a single orifice on the parafrenular papilla. 



(b) The greater sublingual gland (2) fonns a small pear-shaped 

 structure lying superficially on the lateral surface of the lesser sub- 

 lingual mass. It and its duct, whose course and termination have just 

 been described, are filled by the injection from the single papillary 

 orifice in common with the subma.xillary {4). For the sake of consis- 

 tency, and in order to facilitate the subsequent general comparative 

 analysis, the gland and its duct have been colored in Fig. 2 in accord- 

 ance with the scheme (blue) adopted throughout. The terminal seg- 

 ment common to submaxillary and sublingual ducts {4) has been 

 distinguished by the complementary green color. 



The topographical position of the greater sublingual gland, on the 

 lateral, instead of the medial surface of the alveolingual mass, in the 

 specimen here figured and described, is aberrant, and depends evi- 

 dently on individual and very unusual variation. In four other ex- 

 amples of the same species, the greater sublingual gland occupied the 

 typical position under cover of the lesser sublingual mass and on the 

 latter's medial surface. In all of these specimens the short sublingual 

 duct joined the main submaxillary duct, the two terminating by a 

 single common orifice. 



I have figured and described this aberrant chimpanzee here, rather 

 than one of the normal individuals, because the topographical dis- 

 placement of the greater sublingual gland to the lateral, instead of to 

 the medial side of the lesser sublingual mass is one of the supports of 

 the genetic theory of the intermandibular salivary development which 

 will be advanced after the actual conditions in the individual types ex- 

 amined have been recorded (cf. Part IV). 



(c) The lesser sublingual group of glands (j) extends, in this in- 

 dividual chimpanzee, along the lateral aspect of the subma.xillary duct, 

 between it and the greater sublingual gland, dorsocephalad to the 

 lingual nerve intersection. A httle beyond the caudal pointed ter- 



