~, 
180 MONOGRAPH OF BRITISH LAND AND FRESHWATER MOLLUSCA. 
Susp-Genus Discus Fitzinger. 
Pyramidula rotundata (Miiller). 
1692 Cochlea terrestris compressa, maculata, et leviter striata D. Dale, Lister, Hist. 
Conch., App., tabl. 4, gen. tab. 1058, fig. ILA. ; ; 
1695 Planorbis hortensis minima, pulchre striata Petiver, Gazophylacion, tab. 31, fig. 5. 
1712 Cochlea parva magis compressa umbilicata quingue spwrarum pullo et sub- 
flavo colore eleganter tesseliata, striis capillaribus transversé depicta 
Morton, Northamp., p. 416, ch. 17. ; 
1742 Cochlea terrestris depressa et umbilicata, albida, fascia punctata rufa per 
medium anfractuum et maculis concoloribus eleganter depicta Gualtieri, 
Conch., I., tab. 3, fig. Q. 
1774 Helix rotundata Miiller, Verm. Hist., ii., p. 29, no. 231. 
1778 — radiata Da Costa, Brit. Conch., p. 57, pl. 2, ff. 33, 34. 
1828 — turtoni Fleming, Brit. Anim., p. 269. * ? 
1855 — (Delomphalus) rotundata Moquin-Tandon, ii., p. 107, pl. 10, ff 9-12. 
1833 Discus rotundatus Fitzinger, Syst. Verz., p. 99. 
1837 Patula votundata Held, Isis. 
1837 Euryomphala rotundata Beck, Ind. Moll., p. 9. 
1840 Zonites rotundatus Gray, Turton’s Man., p. 165, pl. v., f. 44. 
1852 — radiatus Leach, Syn. Moll., p. 74. 
1893 Pyramidula rotundata VPilsbry, Manual of Conchology, part 33, p. 46. 
ISTORY.—Pyramidulu rotundata (ro- 
tundata, rounded) has been known from 
the earliest times, having been noticed 
by Lister, Petiver, and other of the older 
writers, but was first binomially distin- 
guished by Miiller in 1774. 
It belongs to the section or sub-genus 
Discus of Fitzinger, which is character- 
ized by its depressed spire, convex or 
rounded whorls, and their conspicuous 
rib-striation ; a feature most developed 
upon the upper surface and within the 
umbilicus. 
Some systematists place Pyramidula 
rotundata in the section Gonyodiscus of 
Fitzinger, which differs from Déscws in 
the periphery of the whorls being 
= sharply and distinctly angulated, but 
OL .1110 quar - Sandon Vitzinger himself defined the allocation 
of this species. 
This beautiful little species is asso- 
ciated with Prof. A. Moquin-Tandon, 
of Toulouse, the accomplished author of 
the elaborate work on the Land and Freshwater Mollusca of France, 
which, although published over a half-century ago, is still the most 
esteemed authority upon the land and freshwater mollusca of that country. 
The P. brocchiana and P. cupaniana of Caleara are said by Reinhardt 
to be founded upon young shells of P. rotundata, and according to Dr. 
Pilsbry the genus A/lery«e was established by M. Bourguignat upon 
embryonic shells of this species, 
