﻿U. 
  S. 
  NATIONAL 
  MUSEUM 
  

  

  PROCEEDINGS, 
  VOL. 
  103. 
  PLATE 
  4 
  

  

  Differences 
  in 
  the 
  cl\'peai 
  horn 
  in 
  Bolbocerastes: 
  Upper 
  left, 
  B. 
  serratus 
  (LeConle); 
  upper 
  

   right, 
  B. 
  regalis, 
  new 
  species; 
  lower 
  left, 
  B. 
  impenalis, 
  new 
  species; 
  lower 
  right, 
  B. 
  

   peninsularis 
  (Schaeffer). 
  

  

  