SALIVARY GLANDS OF LOWER PRIMATES 95 



salivary glandular development in the alveolingual region of the 

 lower primates behave as follows : — 



I . The submaxillary line. — The submaxillary gland complex is 

 the largest and most highly developed of the entire series in the lower 

 primates. The main gland occupies the typical position below the 

 mylohyoid muscle in the submandibular recess. The duct extends 

 thence around the caudal border of the mylohyoid forward along the 

 floor of the mouth, occupying the innermost of the three alveohngual 

 lines above described. The supra-mylohyoid portion of the main 

 duct (/) receives, in certain species, the ducts of secondary and 

 accessory glands (/' and /"), which present the following general 

 arrangement : — 



(/') Secondary submaxillary gland. — This is a separate and distinct 

 supramylohyoid gland, situated above the main gland between the 

 caudal margin of the mylohyoid muscle and the point of intersection 

 of the main submaxillary duct with the lingual nerve. The duct of this 

 secondary gland follows the course of the main duct, dorsal to and 

 closely connected to it. The two ducts unite at a variable point 

 caudal to the phca sublingualis, upon which they open through a 

 common shorter or longer terminal segment by a single parafrenular 

 orifice. While such a condition is quite conceivable and may exist 

 in certain forms or in variant individuals, I have encountered among 

 the lower primates heretofore examined no instance in which the duct 

 of this gland attained a separate paraphcal orifice. In every case in 

 which the secondary submaxillary gland and duct were present the 

 latter joined the main submaxillary canal. The length of the terminal 

 duct segment common to the secondary and main submaxillary ducts 

 varies in the different species possessing the secondary gland. The 

 same appears as an occasional component of the adult human inter- 

 mandibular salivary complex (cf. supra. Part I, page 14, Figs. 7 and 9). 



(/") Accessory submaxillary glands. — By this term we define small 

 glandular masses studding the course of the main submaxillary duct 

 and opening into the same by short single or multiple ducts. These 

 accessory glands may be either pre- or post-lingual, i.e. either in front 

 or behind the point of intersection of the main submaxillary duct and 

 the lingual nerve. They may be single, or double, or multiple. The 

 highest number of separate ductules leading from these glands into 



