Part II - State of New Jersey

CRETACEOUS FOSSILS(7) Eutrephoceras tlton~i Reeside, 1927, U. S. Geol. Surv., Prof. Pap.151, pp. 7-8, chart opp. p. 2, pl. 44, figs. 1,2.(?) Eutrephoeeras sp. Reeside, 1927, Ti. S. Geol. Surr., Prof. Pap. 150,pp. 1,2, pl. 1, figs. 1-4.Eutrephoceras dekayl Spath, 1933, Biol. Review., 1'01. 8, p. 431.Et~trephoceras dekayi Stephenson, 1!141, Texas Univ. Publ. 4101, p. 398.(?) Estvephoceras pla?wventer Stephenson, 1941, Texas Univ. Publ.4101, pp. 25, 397-398, pl. 75, figs. 1-6; pl. 76, figs. 9-11.(h) Eutrephoceras spp. Stephenson, 1941, Texas Univ. Publ. 4101, p.398.E?itrephoccra.q dekayi s. 1. Miller, 1947, Geol. Soc. Am., Mem. 23, pp.26-27.When illorton established this species, he gave only a few notes inregard to it, but he illustrated a specimen which has come to be regardedas the holotype. Fortunately, it has been preserved, andthrough the courtesy of Dr. Horace G. Richards it has been made availableto us for study (pl. 65, figs. 5, 6).This specimen, which has been somewhat restored, appears to representan almost complete body chamber preserved in dark-colored"greensand marl.'' Its maximum overall measurement is about 8 em.,and at its adoral end its conch attains a maximum height and correspondingwidth of about 48 mm. and 80 mm., respectively. Theadapical end of this holotype is hounded by a septum, the size and shapeof which are cluci~lated by text figure 1E.The conch is suhglobular, rapidly expanded orad, and broadlyrounded ventrally and laterally. It is more or less semicircular in crosssection but is impressed dorsally to a little more than a third its height.The lateral margins of the aperture seem to be slightly flared.Traces of fine growth lines on remnants of the test show that the aperturebears a wide, moderately deep, broadly rounded, ventral sinus andon either side of it a similar hut narrower and less broadly roundedlateral salient which extends to the umbilicus.The umbilicus is small, closed, and inconspicuous. The umbilicalshoulders are rounded and indefinite.The external suture is almost straight and directly transverse. However,it forms very slight hut nevertheless distinct ventral and laterallobes. The siphuncle is small and subcentral but is distinctly nearer thedorsum than the venter.The immediately preceding paragraphs refer specifically lo illorton'sholotype, but we have under consideration a large number of specimensfrom a variety of Upper Cretaceous horizons at many widelyseparated localities in the United States. The individual representedby figures 1 and 2 on plate 66 is essentially complete and free from distortion.Its adoral camera is shorter than the preceding ones, indieatingthat it had reached full maturity; and the apcrtural margins areslightly hut distinctly flared and are parallel to the grorvth lines. whichNEW JERSEY GEOLOGICAL SURVEY