862 



HISTORICAL GEOLOGY. 



species. The Ammonites Leivesiensis Mant., from the Lower Chalk of 

 England, has a diameter of a yard. 



Cephalopods, Ammonite Family. — Fig-. 1458, Orioceras Duvalii ; 1469, Ancyloceras Matheronianum , 

 1460, Hamites attenuatus ; 1461, Toxoceras bituberculatum ; 1462, Turrilites catenatus. 



Vertebrates. — 1. Fishes. — The earliest of the Teleost Fishes are first 

 known from remains in the Middle Cretaceous, and with them were Sharks 

 of modern as well as ancient type, with numerous Ganoids. Among Teleosts, 

 the Salmon family was represented by species of Osmeroides (Fig. 1463), 



1463. 



Teleost. — Osmeroides Lewesiensis (x J). 



8 to 14 inches long ; the Perch family, by species of Beryx; the Herrings, by 

 species of Clupea; Mackerels, by several species; the rapacious Saurodonts, 

 by species of the American genera Saurocephalus, lehthyodectes, Portheus, 



