TABLE VIII. 



■ , ■ • a: 



INOCERAMUS AND AMMONITE, FROM THE CBETACEOUS FORMATION OF NEBRASKA. 



Medal-rolcd on Pleel, I'lOin llie Original Specimejis. 



Tab. VIII. A, Fig. 1. Iiioronmiis Nebrasrcitsis (N. S.) Sage Creek, Nebraska. 



Before tbis fossil was engraved, it was tliougbt to be altogether impracticable to execute a subject of so great 

 couvexily by the medal-rnling process, aiul the plate was undertaken as a mere experiment, which turned 

 out, however, remarkably successful, and gives a wonderfully perfect representation; more perfect 

 indeed, than could be obtained by any other method 6? engraving. 

 " Fig. '2. Anunoniles Nebrascensis. Fox Hills, Neliraska. 



