284 
DEVONIAN FAUNA. 
? 1844!. Pleurotomaiua Beaumonti. Ooldfms. Petref. Germ., vol. iii, p. 62, 
pi. clxxxii, fig. 8. 
— Orbigntana. Ibid., p. 65, pi. clxxxiii, fig. 3. 
1853. — DECTIS8ATA, Sandhercjer (pars). Verst. Ehein. Nassau, 
p. 196, pi. xxiv, figs. 1, 1 a, 1 h. 
1853. — DECussATA, var. elegans, Sandberger. Ibid., p. 196, 
pi. xxiv, figs. 3, 3 a — d. 
1853. — DECTJS8ATA, var. GEMINATA, Sandberger. Ibid., p. 196, 
pi. xxiv, figs. 9, 9 a. 
1885. — Orbignyana, Maiirer. Kalke von Waldgirmes, Darm- 
stadt, p. 234, pi. X, fig. 3. 
1889. TuEBO cf. Oebigntanus, Barrois. Faun. Calc. d'Ebray, p. 216, pi. xv, 
figs. 7, a, b. 
1889. Pleueotomabia d'Orbigniana, Whidborne. Greol. Mag., dec. 3, vol. vi, 
p. 30. 
Descri/ption. — Shell very small, turbiniform, dilate, few-wliorlecl. Spire conical, 
rather elevated, of three or four rather broad convex whorls. Suture deep, obtuse. 
Whorls horizontal at the suture, but immediately sloping obliquely downwards in 
a convex curve to the lower part, and there curving more rapidly inwards to the 
lower suture, or, in the case of the body-whorl, to form an obliquely flatfish base. 
Sinus-band low down, being immediately above the suture in the upper whorls, 
and just below the widest point of the shell in the body-whorl, not elevated, broad, 
with low bounding ridges. Ornament consisting normally of eight distant spiral 
threads, similar to the ridges, above the sinus-band, and eleven below it, which 
are occasionally alternating or undeveloped ; the upper part of the shell being thus 
divided into about five shallow grooves similar to the sinus-band, and the lower 
part into eight or nine which are closer ; the whole crossed by more, and generally 
much more, numerous stout rounded threads, which slope obliquely back from the 
suture at an increasing angle till they reach the sinus-band, in which they curve 
round, and then proceed perpendicularly across the next grove, then tend rather 
backwards, and then again become perpendicular at the centre of the base. 
Umbilicus minute, aciculate, twisted. Inner lip not diffuse, and not continued to 
the upper angle. Columella longitudinally grooved, slightly arcuate. Mouth 
transversely ovate. Shell-structure rather thick. 
Size. — Height 10 mm , width 10 mm. 
Localities. — There are seven specimens in the Woodwardian Museum which 
were obtained by Mr. B. B. Tawney from Lummaton, and four in the Torquay 
Museum, which probably came from Lummaton and Wolborough. 
Bemarks. — There seems some doubt whether Sandberger's or d'Archiac and 
de Verneuil's name for these shells should have the priority. They were both 
published in the year 1842. Sandberger in his later work gives it to his own 
name; but it is to be noted that d'Archiac's paper was read in December, 1841, 
