68 MOLLUSCA FROM THE GREAT OOLITE. 
Shell small, conical; spire acuminated; whorls rather flattened, and encircled with 
four imbricated striz ; the last whorl is somewhat angulated towards its base. 
The imbricated striz are fine and closely arranged, those beneath the angle upon the 
last whorl are larger; the aperture is semilunar and contracted. As compared with 
M. decussata, this shell is more lengthened, the apex pointed, and the encircling striz 
much fewer. 
Locality. t is rare, and occurs, with the species before mentioned, at Minchinhampton, 
Monoponta Formosa. Plate XI, figs. 6, 6a, 6. 
M. Testé turbinatd, spird subdepressd, prominuld, obtusa; anfractu ultimo ia medio 
carinato, striis transversis crebris tenuissimis cincto; carind levigatd, rotundatd, obtusd, 
striis supra carinam positis magis elatis ; apertura semilunari subcontracta. 
Shell turbinated, spire rather depressed, small, obtuse; the last whorl carinated in its 
middle part; the carina smooth, rounded, and obtuse; the last whorl has likewise trans- 
verse, closely arranged, fine, and crenulated stria, those above the mesial carina being 
larger than the others ; aperture semilunar, somewhat contracted. 
In the greater number of specimens, more especially those of large dimensions, the 
encircling striz are obsolete, the only markings being the lines of growth. Diameter of 
largest specimens, 43 lines. 
Locality. Jt is abundant and common to all the shelly beds near Minchinhampton. 
Monoponta pecussaTa. Plate XI, figs. 9, 9a. 
M. Testé parvd, conicd; apice obtuso; anfractibus planis, suturis tmpressis; striis 
crebris transversis et longitudinalibus decussatis. . 
Shell small, conical ; apex obtuse ; whorls flattened, their sutures impressed, encircled 
with numerous transverse strize, decussated and impressed by others longitudinally. 
This shell is more obtuse than JZ. imbricata; the last whorl is more cylindrical than 
the others ; the lines upon its surface are so delicate as to be scarcely visible, unless under 
a magnifier. 
Locality. Vt is rare, and occurs with J. cmbricata, in the soft shelly Oolite of 
Minchinhampton Common. 
Monoponta Lasapyet, Archiac, sp. Plate XI, fig. 2; var. fig. 11, lla. 
Trocuus LapapyeEt, Archiac. 1843. Mém. Soc. Géol. de France, iii, p. 379, t. 29, 
figs. 2, 2a. 
TURBO — D’ Orb, 1850. Prod. Paléont., p. 301. 
? MonoponTa LHvIGATa, Goldfuss. Petref., p. 101, t. 195, fig. 5. 
2? Turzo Destonccuampsi, Desh. Elem. de Conchyl., t. 68, figs. 17, 18. 
