MONOGRAPH OF BRITISH LAND AND FRESHWATER MOLLUSCA. 141 
Zonitoides nitidus (Miiller). 
1774 Helix nitida Miller, Verm, Hist., ii., p. 32, no. 234. 
1789 — nitens Gmelin, Syst. Nat., p. 3633. 
1789 = — sueccinea Studer, Faun. Helvet. in Cox’s Travels, iii., p. 249. 
1I80L = — nitida Draparnaud, Tabl. Moll., p. 96. 
1805 lucida Draparnaud, Hist. Moll., p. 103, pl. viii., ff. 11, 
1826 Beisel nitida Risso, Hist. Nat. Eur. Merid., iv., p. 72. 
1837 — _ sueceinea Beck, Index Moll., p. 7. 
1858 — lucida Bellars, Ill. Cat. Br. L. & F. W. Shells, p. 16, pl. 2, f. 38. 
1833 Oxychilus lucidus Kitzinger , syst. Verz., p. 100. 
18384 Tanychlamys lucida Benson, Proe. Zool. Soc., p. 89. 
1837 Polita lucida Held, Isis. p. 916. 
1840 Zonites lucidus Gray’s Turton, p. 174, pl. 4, f. 38. 
1853 — nitidus Lowe, Moll. Notts., p. 69, ff. 43, 44. 
1855 — (Aplostoma) nitidus Moquin- Tandon, it., p. 72, pl. vii., ff. 11-15. 
1871 Hyalina (Euhyalina) nitida Wobelt, Catal. Eur. Binnenconeh., p- 5. 
1877 Hyalinia nitida Westerlund, Faun. Eur. Moll., p. a 
1873 Zonitoides nitidus Lehmann, Moll. Pommern, ?. TING Se3q 1 By 
ISTORY.—'This species was first 
described by Miiller in 1774, and 
in 1801 Prof. Draparnaud in his 
“Tableau” recognised it as a French 
species, and adopted Miiller’s name 
but in the ‘ History,” published dee 
1805, after his death, great confusion 
has been caused by the name being pur- 
posely or accidentally transposed with 
that of yalinia lucida. 
It is the Helix hydrophila of Ingalls, 
the Helix tenuis of Dillwyn, and accord- 
ing to Tryon the //. nitescens of Andaz. 
With this species is associated Mr. 
W. Moss, of Ashton-under-Lyne, who is 
not only an able conchologist, but a 
skilful anatomist, and an accomplished 
adapter of the photographic camera and 
microscope to the needs of the study. 
He first detected the presence of the 
calcareous penial plates in Zon/tocdes, 
and has elucidated and confirmed many important anatomical details in 
the present and other species. 
Diagnosis.— Zonitoides nitidus may be distinguished from its congener 
Z. excavatus by its narrower umbilicus and its rich deep-brown colouring. 
From Hyaliniu nitidula it differs in the total absence of the white basal 
opacity, greater convexity, and darker colour. From HZ. radiatula it 
differs in its much larger size, but is more difficult to separate when 
young ; it is, however, more globose, has fewer whorls, and the striation 
is more markedly irregular. 
INTERNALLY, the lime-charged arterial vessels, especially of the hepatic 
region, which form such striking and beautiful tracery upon the darkly- 
coloured external surface of that organ in Zonitoides excavatus, are in the 
present species scarcely apparent. 
