8MITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 81, NO. 1, PL. 23 



FIGS. 1 & 2— CERATOTHERIUM SIMUM COTTON I ; MALE 

 FIGS. 3 & 4.-CERATOTHERIUM SIMUM COTTONI ; FEMALE 

 SHOWING AGE AND SEXUAL DIFFERENCES IN DEVELOPMENT OF THE NASAL BOSS 



