cxviii INFERIOR OOLITE AMMONITES. 



Description. — Subgraclumbilicate, costate. 



Locality and. Stratum. — The locality of an unlabelled specimen is presumably 

 Somerset : Stoford, from well-grained ironshot — my father's collection. Another 

 specimen, showing costate umbilicus, Bradford Abbas, Dorset, Collection Damon. 



Bate of Existence. — Discitse hemera, presumably. 



2. Deltoidoceeas asteictum, 8. Buchman. Suppl., Fig. 81 in text. 



Description. — Subconcavumbilicate, costate. 



Distinction. — From D. idoneum, the narrower periphery; the more compressed 

 whorls ; the smaller umbilicus. 



« 



Fig. 81. — DcUijulocems astrictm 



Locality and Stratum. — Dorset : Bradford Abbas, in a bluish matrix, from 

 the Fossil Bed. 



Date of Existence. — Discitse hemera. 



3. Deltoidoceeas subdiscoideum, S. Buchman. Plate XIX, figs. 5, 6 (type); 



Plate XX, figs. 1, 2. Suppl., Fig. 82, p. clxv. 



1889. Hyfeklioceras subdiscoideum, This Monogr., PI. xix, figs. 5, 6; PI. xx 



figs. 1, 2. 

 1902. Deltoidoceras subdiscoideum, Emend. Amm. Norn., p. 3. 



Description. — Subgradumbilicate ; obscuri-subcrassicostate to levigate. 



