LIFE HISTORY OF DESMOGNATHUS FUSCA. 



313 



its distal (posterior) end; the other gland, which opens near 

 the ventral angle of the naris, is also well developed, extends 

 nearly as far posteriorly as the first but in a more ventral location, 

 and as yet shows no branching. Although other glands of the 



lilt 



FIG. 1 8. Horizontal sections through the nasal region of (a) Desmognathus fusca 

 larva collected in February, and (b) an individual immediately after the com- 

 pletion of its metamorphosis, for comparison of the glandular development; ac, 

 acinous glands of adult stage; d, duct of the most dorsal of the naso-labial glands 

 (nlj); int, intermaxillary glands; men, and mdn, musculus constrictor naris, and 

 musculus dilatator naris respectively; nli, the first nasolabial gland; ns, external 

 naris; or, orbital glands. Drawn with Abbe camera. X 32-5- 



group are slightly developed, none of the tubules have as yet 

 become so extensive as to enter either the premaxillary foramina 

 or the grooves of the maxillary bones as they are to do later in 

 the fully developed adult. Simultaneously with the development 

 of these naso-labial glands the muscular apparatus for opening 



