PLEUROTOMARIA. 431 
372, PLEUROTOMARIA ORNATA-DEPRESSA, Sp. nov. Plate XX XIX, figs. 3 a—c. 
Cf. Cirrus cartnatus, Sowerby. Min. Conch., pl. cccexxix, figs. 3, 4. 
Description : 
Height : : 3 ° . 14mm. 
Basal diameter : 4 : . 40 mm. 
Spiral angle . F : ‘ s (135%. 
Shell turbinate, subdiscoidal, umbilicate. Spire regular. Whorls (about five) 
angular and discoidal; sutures strongly canaliculate. The spiral ornamentation 
is well developed, and, in addition, the crown of each whorl carries a zone of 
undulating radial tubercles regularly disposed. 
The sinus-band is wide, median and flat, with traces of spiral lines, which, 
however, are not seen anteriorly. The body-whorl is relatively large and similar 
in character to the whorls of the spire, with an angular periphery and flattish base 
richly decussated ; umbilicus deep rather than wide. Aperture oval-depressed. 
Relations and Distribution.—The figured specimen is from Bradford Abbas 
most probably from the Concavus-bed. Small depressed forms, with somewhat 
similar ornamentation, occur in the Murchisone-zone of the Cotteswolds; I also 
possess a cast from Leckhampton which corresponds well with this figure. PI. 
ornata-depressa may be regarded as the most depressed variety of the Ornata-group. 
A large specimen showing similar ornamentation, but with a rounder body-whorl 
and rather higher spire, presents us with another variety of the Ornata-group. 
This is from Dundry. 
Note respecting Cirrus carinatus.—It will be remembered that this very 
discoidal cast came from Leckhampton. Presuming that it is the cast of a 
Pleurotomaria, this makes one of the three Jurassic species of which the actual 
figured specimen is preserved in the Sowerby type collection at the British Museum. 
Unfortunately, the name “ carinata”’ as applied to Plewrotomaria is bespoken 
for a Paleozoic fossil, viz. Plewrotomaria (Helix) carinata, Sowerby (‘ Min. Conch.,’ 
pl. x, upper and lower figures). 
373. Purvrotomaria Actma, d’Orbigny, 1850. Plate XXXVII, fig. 8. 
1850. Prevroromarta Acrma, d’Orbigny. Prod., i, p. 267. 
1854. — — — Terr. Jur., vol. il, p. 459, pl. ccelxxv. 
1873. _— — — Tawney, Dundry Gasteropoda, p. 50 
(42). 
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