96 



PISCES 



CLASS I 



Family 5. Saurodontidae. Cope (non Zittel). 



Skull laterally compressed ; jaws poweiful, and bearing a single row of compressed, 

 hiife-like teeth, with nutrient foramina or notches helow the internal alveolar border ; 

 a presymphysial bone present and without teeth, Cretaceous. 



The two genera constituting this faimily, ßaurocephalus, Harlan (non Ag.), 

 and Saurodon, Hays (Daptinus, Cope), difFer from the Ichthyodedidae in the 

 presence of a presymphysial bone and in the form and manner of succession 

 of teeth. In the first-named genus the cr(^ns of the teeth are short and 

 compressed, with nutrient foramina below the alveolar border on the inner 

 face of the jaw ; and in Saurodon the inner margin of each dental alveolus 

 is deeply notched. Upper Cretaceous ; New Jersey and Kansas. 



Family 6. Olupeidae. Herrings. 



Trunk elegantly fusiform. Supraoccipital bone separating parietals, and otic' 

 region prominent; cheek plates reduced ; premaxilla very small ; maxilla large, 

 entering the gape, loith two supramaxillaries ; dentition feeble. Opercular apparatus 

 complete, but few branchiostegal rays, and no gular plate. A single dorsal ßn, nearly 

 median, without adipose dorsal. Scales thin and cycloid, without bony layer. Lower 

 Cretaceous to Recent. 



Diplomystus, Cope. Abdomen compressed to a sharp edge, and bordered 



with large ridge scutes ; back between the occiput and dorsal fin armoured 



with smaller ridge scutes. D. dentatus, Cope, and other species finely preserved 



in the Eocene Green River Shales of Wyoming, U.S.A. Smaller species in 



the Upper Cretaceous 

 of Mount Lebanon 

 (B. brevissimus, Blv. 

 sp.) and Brazil, and in 

 the Oligocene of the 

 Isle of Wight. Living 

 in the rivers of New 

 South Wales and 

 Chili. 



Scombroclupea, 



Kner. As Clupea, but finlets spaced out between the small anal and the 



forked caudal fin. 



S. macrophthalma, 



Heckel sp., from 



Upper Cretaceous 



of Mount Lebanon 



and Comen, Istria. 

 Clupea, Linn. 



Herrings. (Fig. 



172.) Abdomen 



compressed to a 



sharp edge, and 



Fig. 172. 



Clupea ventricosa, H. v. Meyer. Lower Miocene ; Unterkirchberg, 

 near Ulm, Würtemberg. 



Fig. 173. 

 Mcletta sardinitea, Heckel. Lower Oligocene 



bordered with large ridge scutes ; no dorsal scutes. 

 jaws and palatines, larger on the vomer and hyoid. 



Radoboj, Croatia (after Heckel). 



Teeth minute on the 

 Dorsal fin small and 



