I08 SALIVARY GLANDS OF LOWER PRIMATES 



dary parallel channel (/'). the duct of the secondary submaxillary gland. 

 Moreover, the main submaxillary hne is capable of furnishing by 

 subsequent sprouting additional glandular components, the accessory 

 submaxillary glands (/"), the latter opening by short ducts directly 

 into the main channel. 



Both of these additional components may develop side by side 

 {Lagolhrix, Figs. lo and 13; Ateles, Figs. 11 and 25), or only one of 

 them may appear {Ateles, Figs. 9 and 15 ; Macacus, Figs. 7 and 22 ; 

 Cynocephalus, Figs. 2, 4, 3, and 5; Figs. 19, 20, and 21). 



The intermechate district (2) does not always develop glandular 

 elements in the lower primates. It is the site of origin of the incon- 

 stant component here described as the greater sublingual gland. A 

 glance at the series of schemata of the individual types selected will 

 show its distribution in the order and its general relations. 



In the anterior region the terminations of the individual ducts on 

 the parafrenular papilla deserve special notice. 



Three conditions may be encountered : — 



A. The main and secondary submaxillary ducts join into a shorter 

 or longer common terminal piece, which opens by a single orifice on 

 the sublingual papilla. This, according to our observations, is inva- 

 riably the arrangement found in instances in which the secondary 

 submaxillary gland develops (e.g. Lagolhrix, Figs. 10 and 16; Ateles, 

 Figs. II and' 25; Macacus, Figs. 7 and 24). Genetically it must be 

 assumed that the subdivision of the submaxillary crest, responsible 

 for the production of the secondary parallel duct, ceases anteriorly 

 behind a common area still included in the forward extension of the 

 duct and destined to form the terminal segment common to both. 

 The greater sublingual gland, if present, has a separate papillary 

 orifice, lateral and a Uttle caudal to the main submaxillary opening. 

 It is to be noted that we have encountered no instance in our series 

 of lower primates in which, with the development of both secondary 

 submaxillary and greater subhngual glands, the orifice of the terminal 

 duct segment, common to the former and to the main submaxillary 

 duct, opened side by side with that of the subhngual duct. 



B. This condition has been, therefore, only found by us in forms 

 in which the secondary' submaxillary duct does not develop, and in 

 which the main submaxillary duct is either simple {Macacus cynomol- 



