8 



INEZ L. WHIPPLE. 



In two regions the naso-labial glands come into close proxim- 

 ity with other glands of such similar structure that the determi- 

 nation of the actual relationship is very perplexing. One, at 

 least, of the mesial tubules (Figs. 2 and 6, nip), 1 turns dorsally 



nc 



nl 



FIG. 6. Transverse section through head of adult Desmognalhus fusca (X 4 2 ), 

 showing the naso-labial groove cut obliquely and the horizontal groove (grl) cut 

 transversely. fi, premaxillary bone. Other designations as in previous figures. 



before reaching the mid-line and enters the foramen for the 

 internal nasal branch of the ophthalmic nerve at the anterior end 

 of the premaxillary bone. Through this foramen the tubule 

 may be traced as far as the opening of the foramen into the 

 intermaxillary space. In this space lie the much convoluted 

 tubules of the intermaxillary gland (int), the orifice of which is 



in the mid-line of the roof of the mouth, a little anterior to the 

 posterior nares. In the larger specimens the naso-labial tubule 

 passes into the intermaxillary space and intermingles its convo- 

 lutions with those of the intermaxillary gland. I have found it 

 impossible from my preparations to determine whether the 

 tubules of the two glands thus curiously intertwined become 

 actually continuous or not. If such an anastomosis exists, how- 

 ever, it is certainly established secondarily, for in small adults 

 the naso-labial tubule has not reached the intermaxillary space 

 but ends blindly within the foramen, and there is consequently 



1 In every case in which I have been able to demonstrate the relationships of this 

 tubule with absolute certainty, it has proved to be one of the branches of the gland 

 which opens on the ventral margin of the naris 



