Ifesozoic and Caniozoic Geology and PaJa'ontolog'y. • 45 



In 1829, Div, Morion illustrated a section of Cretaceous rocks, 27 8-12 

 feet in height, found in a bluff, on the margin of Crosswick's Creek, New 

 Jersey, and separated the Cretaceous of New Jersey and Delaware in- 

 to the lignite strata and the marl. He relied, in determining the 

 Cretaceous age of the rocks, upon the genera Terehratula, Gryphoia, 

 Exogyra, Ammonites^ Baciilites and Belemnif.es. He described,* from 

 an excavation for the Delaware and Chesapeake canal, Ostreafalcata, 

 and from other places, Terehratula hai'lani, T. fragilis^ T. sayi.^ 

 Gryphoea niiUabilis and G. vomer. 



In 1830, f he published his Synopsis of the Organic Remains of the 

 Ferruginous Sand Formation of the United States, with geological re- 

 marks. He treated of the distribution of the strata, and mentioned 

 many localities in the eastern and southern States where they are ex- 

 posed, and also discussed the mineralogical characters of the marls. He 

 described 5eZem?l^7es americanus, B. ambiguus, Cucullcea vulgaris., now 

 Idonearca vulgaris., Ammonites delatoarensis, A. vamixenii, Spatan- 

 gus Stella, Ananchytes cruciferus., A. cinctus, A. Jimhriatus and An- 

 thophyllum atlanticum, now Jlontivaltia atlantica. He also deter- 

 mined that two species, figured in Sowerby's Mineral Conchology, under 

 the names of Chama heliotoidea and (J. conica, belong to Say's genus 

 Kxogyra. Sowerby soon after adopted his determination, which was 

 the first instance in which the genus of an American author was 

 adopted in Europe, where it required the separation of the species 

 which had been referred to an older genus. 



In 1833,+ he published a Supplement to his Synopsis, in which he il- 

 lustrated and described Bostellaria arenaria, now Anchiira arenaria, 

 Tornitella bullata. Conns gyratus, Cytherea excavata, now CypiHmeria 

 excavata, Cardita decisa, Clavagella armata, Flagiostoma gregale, 

 now Spondylus gregalis, P. pelagicum, now Lima pelagica, Pecfen 

 jyei'plamis, P. venustus.^ Anomia argentaria, GrypJicea plicatella, Os- 

 trea falcata, var. nasuta, 0. mesenierica, 0. tortuosa, 0. urticosa, 



* Jour. Acad. Nat. Sci., vol. 6, part 1. 

 t Am. Jour. Sci. & Arts., vols. 17 & 18. 

 t Am. Jour. Sci. & Arts., vols. 23 & 24. 



