EXPLANATION OF PLATE XXVIII. 

 NASUA NARICA MOLARIS Merriam. 



Figures all | nat. size. 

 Ventral view of the 6 specimens shown in Plate XXVII. 



FIG. i. 9 juv., same skull as shown in Fig. i, PI. XXVII. 



FIG. 2. cT juv., same skull as shown in Fig. 2, PI. XXVII. At this stage 

 of growth there is very little sexual difference in the skull, beyond the distinctly 

 larger size of the male. 



FIG. 3. Middle-aged 9 , with the teeth still practically unworn. Same 

 skull as shown in Fig. 3, PI. XXVII. 



FIG. 4. Young adult cT, probably a year or so younger than the female 

 shown in Fig. 3, as indicated by the sutures being still open. Note the heavier 

 dentition in the male skull, particularly the much larger canines, while the 

 general contour of the skull is practically the same in both. 



FIG. 5. A very old 9 , for comparison with the very old male shown in 

 Fig. 6. Same skull as shown in Fig. 5, PI. XXVII. 



FIG. 6. A very old tf, for comparison with the old female, a young male, 

 and a middle-aged female shown respectively in Figs. 5, 4, and 3. Note especially 

 the greater depth of the postorbital constriction, the lessened width of the post- 

 maxillary portion of the palatal region, and the much wider and more angular 

 zygoma. 



