36 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



EXPLANATION OF PLATES. 



All figures are of tlie natural size, and tlie originals are preserved in the 

 Museum of Comparative Zoology. 



PLATE 1. 



Figs. 1-3. Histionotophorus hassani (Zigno). Upper Eocene ; Monte Bolca. Figs. 1 



and 1 a are counterparts of tlie same specimen. 

 Fig. 4. Caranx primaevns, sp. nov. L'pper Eocene; Monte Bolca. 

 Fig. 5. S i/mp/iod us szajnochae {Zigno). Upper Eocene ; Monte Bolca. 



PLATE 2. 

 Pi/gaeus agassizil, sp. nov. Upper Eocene; Monte Bolca (ex Canossa Collection). 



