44 CRETACEOUS LAMELLIBRANCHIA. 
Genus—Graumatovon, Meek and Hayden (1860), 1864." 
[‘ Proc. Acad, Nat. Sci. Philad.,’ 1860, p. 419 (list name) ; “ Paleontology of the Upper Missouri,” 
‘Smithsonian Contrib. to Knowledge,’ vol. xiv, No. 172, 1864, p. 89, pl. ii, fig. 9.] 
Grammatopon sucuris (Leymerie), 1842. Plate VII, figs. 14a, b, 15a, b; Plate 
WII, figs 2: 
1829. Cucurima, J. Phillips. Geol. Yorks., pt. 1, p. 186, pl. ii, fig. 16. 
1842. — sEcuURIS, A. Leymerie. Mém. Soc. Géol. France, vol. v, p. 6, 
pl. vii, figs. 6, 7. 
1844. Anca securis, A. d’Orbigny. Pal. Franc. Terr. Crét., vol. iii, p. 208, 
pl. eecix, figs. 9, 10. 
1845. — — E. Forbes. Quart. Journ. Geol. Soc., vol. i, p. 246. 
1850. — — A, d’Orbigny. Prodr. de Pal., vol. 11, p. 80. 
11854 — = J. Morris. Cat. Brit. Foss., ed. 2, p. 185. 
1855. — _ G. Cotteau. Moll. Foss. de l’Yonne, p. 87. 
1861. — - P. de Loriol. Anim. Invert. Foss. du Mont Saléve, p. 86, 
pl. x, fig. 8. 
1866. — _ F. J. Pictet and G. Campiche. Foss. Terr. Crét. de Ste. 
Croix (Mater. Pal. Suisse, ser. 4), pt. 3, pp. 443, 469. 
1875. Cucunima secunrts, J. Phillips. Geol. Yorks., pt. 1, ed. 3, p. 328, pl. ii, 
fig. 16. 
1896. Arca sEcurIs, A. Wollemann. Zeitschr. d. deutsch. geol. Gesellsch., 
vol. xlviii, p. 845. 
Measurements : 
Length : : ; : . : : - ail mm: 
Height : : . : 5 : : 2 lt 
Thickness . ; : 5 RS 
; f . é 
Affinities —This form, as was pointed out by de Loriol, is very similar to 
Grammatodon carinatus (Sowerby) (see p. 45), and I think it is possible that they 
may prove to be identical, but until more specimens have been obtained I shall 
regard the two as distinct. In G. secwris the area appears to be broader 
than in G. carinata ; and also on the left valve of the former the ribs are more 
widely separated than in the latter, and there are small ribs in the interspaces. 
Cucullea Schiisteri, Roemer,’ is perhaps an allied form, but I have seen no speci- 
men of it. 
Remarks.—The specimen figured by d’Orbigny is proportionately longer than 
1 For the synonymy of this genus see Woods, ‘Ann. Mag. Nat. Hist.,’ ser. vii, vol. iii (1899), 
p. 47. To the names there given should be added Beushausenia, Cossmann, ‘ Rev. crit. Paléozool.’ 
(1897), p. 93. 
2 «Die Verstein des nord-deutsch. Kreidegeb.’ (1841), p. 70, pl. ix, fig. 3. 
