27G The Ducts of the Human Submaxillary Gland 



especially the California live oak. That this parallel is not fanciful can 

 be shown by a glance at a corroded preparation of the human submaxil- 

 lary, where Wharton's duct represents the trunk, the interlobular ducts 

 the branches, the intralobular ducts the twigs, and the alveolar am- 

 pullae the foliage. AVhen the injections are incomplete (Fig. 1) they 

 look like the naked limbs of the oak, but if the mass has passed into 

 the alveoli the corrosion resembles that tree in full foliage. In the 

 corrosion preparations the form of the gland is preserved by the tree 

 as a whole, and these naturally vary in the same wide limits noted in 

 the gross relations of the organ. When aberrant lobes or prolonga- 

 tions are present their ducts nsnally look like branches arising from 

 the trunk of a tree some distance below the nsual branching zone. 

 The size of these portions varies a good deal, but in general they may 

 be said to correspond to that part of the gland which is drained by a duct 

 of the first order. 



The submaxillary duct and its ramifications may be classified in the 

 following general scheme, each subdivision representing one of its main 

 divisions, which has, in general, fairly definite relations to the glandu- 

 lar units: 



1. Ductus submaxillaris. 



2. Primary ducts. 



3. Interlobular ducts. 



4. Sublobular ducts. 



5. Lobular ducts. 



6. Intralobular ducts. (Salivary tubes of Pfiiiger.) 



7. Intercalary ducts. 



8. Alveolar ampnlls. 



At the hilus there is a considerable amount of connective tissue 

 through which the duct penetrates as it enters the gland. In most 

 human submaxillaries the duct divides shortly after entering the hilus; 

 in pigs, apparently, it always does. It is not uncommon, however, to 

 observe in human glands instances where the main duct preserves its 

 identity, penetrating directly through the substance of the gland and 

 exhausting itself by manifold lateral branching instead of dividing into 

 several chief primary divisions just after entering the hilus. 



It is somewhat difficult to obtain the diameter of the duct between, 

 the hilus and papilla in corroded specimens owing to the nature of 

 the material used since we employed for this purpose the glands re- 

 moved from bodies in the dissecting room. The walls of the ducts had 

 lost their tonicity and this, together with shrinkage of the celloidin 



