PLEUROTOMARIA. 421 
362. PLEUROTOMARIA SUBDECORATA, Miinster, 1844, Inferior Oolite variety. Plate 
XXXVI, fig. 10. 
1844, PLEvRoToMaRIA suspEcorata, Minster. Goldf., Petref., pl. elxxxv, fig. 3. 
1854. — — — ? D’Orbigny, Terr. Jur., vol. i, 
p- 445, pl. ecelxiv, figs. 1—6. 
1873. _ _ — (? non d’Orb.) Tawney, Dundry 
Gasteropoda, p. 44 (86). 
Description : 
Height j : : . 30 mm. 
Basal diameter : : ; . 40 mm. 
Spiral angle . ‘ : Bell 
Shell turbinate, subturrited, widely initia: Spire regular. Whorls (seven) 
subconvex and rather flattened posteriorly, sutures subcanaliculate in the later 
whorls. The ornamentation is regular throughout, consisting of well-cut and 
slightly undulating spirals, which show beautiful cancellation in the early whorls, 
and a certain amount of radial striping in the posterior area of the later ones. 
The sinus-band is submedian, prominent, and moderately wide, but does not 
constitute an angle; it has spiral ornament similar to that of the whorls, though 
rather closer. he body-whorl is bluntly angular at the periphery ; base sub- 
convex and largely umbilicated with strong spiral and radial ornamentation. 
Aperture subrhomboidal. 
Relations and Distribution.—Near to Pl. subdecorata, M., this form differs in 
having the whorls less angular ; yet, on the whole, conforming to Goldfuss’ rather 
than to d’Orbigny’s description. It belongs to the Fasciate, though with a tendency 
towards the Ornate. 
The figured specimen, from Dundry, is the only one of that size from the Inferior 
Oolite. A much smaller form, about 12 mm. in height, and with six whorls, 
occurs sparingly in the Concavus-bed at Bradford Abbas and in the “ Base bed”’ at 
Lincoln. These specimens seem to be truly micromorphs of Pl. subdecorata, but 
are rather more turrited and with canaliculate sutures. At present we should 
not be justified in constituting a new species. 
