HORSE-MACKERELS. 



441 



Ventrals thoracic, sometimes rudimentary or entirely absent. 

 No prominent papilla near the vent. Gill-opening wide. Ten 

 abdominal and fourteen caudal vertebrm. 



Inhabitants of tropical and temperate seas. Carnivorous. 

 They appear first in cretaceous formations, where they are 

 represented by Flatcw and some Caranx-Klce genera ( Vomer 

 and Aipichthys from the chalk of Comen in Istria). They are 



Fig. 195. — Semiophorus velitans. 



more numerous in various Tertiary formations, especially in 

 the strata of Monte Bolca, where some still existing genera 



