Náttúrufræðingurinn - 1977, Side 25

dalur, S. (Páll Einarsson, 6 specimens
1966).
Zoniloides arboreus (Say): Reykjavík
(Árni Einarsson).
Cepaea hortensis (Miill.): Heimaey, S.
(many collectors).
Two new species are added to the Ice-
landic fauna: Trichia hispida (L.) and
Oxchilus draparnaudi (Beck). Both were
found in Reykjavík by the author and
certainly introduced recently by man.
The record of Cepaea hortensis deserv-
es special mentioning. Lindroth et al.
(1973) state that this species does not live
iti Heimaey and thereby consider the re-
cord of Schlesch in The Zoology of Ice-
land to be erroneous. Cepaea hortensis is
however well known among the island-
ers to live on Heimaey (Klif and Heinta-
klettur). This is confirmed by many
specintens (cf. Einarsson 1970).
Tlie land snails in Iceland can be
grouped in 6 categories according to di-
stribution:
1) Distribution over the whole country
(Vitrina pellucida (Miill.)).
2) Lowland species (Succinea pfeifferi
Rossm., Punctum pygmaeum (Drap.),
Nesovilrea hammonis (Ström), Euco-
nulus fulvus (Miill.)).
3) Soutliern species (Cochlicopa lubrica
(Miill.), Cochlicopa lubricella (Porro),
Vitrea crystallina (Miill.), Vitrea con-
tracta (Westerl.), Oxychilus alliarius
Miller), Aegopinella pura (Alder),
Cepaea horlensis (Miill.)).
4) Nortliern species (Vertigo modesta
arctica Wall., Pupilla muscorum (L.)).
5) Eastern species (Arianta arbustorum
(L.)).
6) Balea perversa (L.). Only found in
Austur-Skaftafellssýsla.
These categories (except no. 5 and 6)
conform well with patterns in the climate
in Iceland when using the oceanic in-
dices calculated by Hallgrímsson (1969,
1970). The distribution of Arianta arbus-
torum and Balea perversa remains un-
explained, but several vascular plants
show the same distribution patterns.
A significant difference is found in the
height of Columella aspera specimens
from N. and W. Iceland versus those
from Öræfi in the SE. (cf. Eig. 6). The
height in N. and W. Iceland ranges be-
tween 2.6 and 2.8 ntm but between 1.8
and 2.2 in Öræfi. Henrik W. Waldén has
kindly confirmed that both fomis belong
to C. aspera.
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