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in form. Length Vis inch (= 1,7 mm.)“. Only one figure, that of the stell seen from the side,
accompanies this general and incomplete description, from which it is only clear that a form
belonging to the family Asteropidae was before the writer. This figure shows an oviform shell
with its greatest height somewhat behind the middle and the posterior part of the shell
comparati velv slightly larger than the anterior part; the proportion of the length to the height is
1,54 : 1; the dorsal and ventral margins are evenly curved, the former distinctly more boldly
than the latter.
These facts obtained from the original description and figure seem to show with all
desirable clearness that Professor G. S. BRADY’s identification of the specimen on which the
species I have described is based as A. teres (A. M. NORMAN) cannot be considered as having
sufficient proof to support it.
Although this species of A. M. NORMAN’s is based only on an incomplete investigation
of an empty shell, subséquent writers have nevertheless succeeded in identifying with it not
only forms that they have investigated themselves, but also forms incompletely described by
other authors and obvionsly not re-examined by themselves. Thus G. S. Brady and A. M.
Norman in their work of 1896 include this species and give the following forms as synonyms
of it: Cylindrolebereis teres, G. S. Brady, 1867 and 1868 a and b, ? Asterope oblonga, C. CLAUS, 1876
and Cylindroleberis teres, G. W. Müller, 1894. — G. W. Müller also includes this species of
NORMAN’s in ,,D as T i e r r e i c h“; as synonyms of it are given: ? Bradycinetus teres, A. M.
NORMAN, 1867, Asterope oblonga and A. ovalis, C. Claus, 1876, Copechaete armoricana -j- C. fissa,
Ë. HESSE, 1878, Cylindroleberis teres, G. W. MÜLLER, 1894 and ? Asterope oculata, G. S. Brady,
1902 a. —
As far as one can see these investigators have followTed the principle of combining into
one species all forms of the genus Asterope which are characterized by having the posterior part
of the shell dominating more or less strongly over the anterior part. It seems certain that
this method of procedure can scarcely be considered justifiable and that it can only be explained
as due to these writers’ deficiency of knowledge of these forms. A study of the species of this
genus that are dealt with in this treatise will show this quite clearly. Compare, for instance,
A. Midleri var. longiseta, A. Oblini and A. curta with the species dealt with above. These species
clearly show that forms quite obviously distinet from one another with regard to the limbs, etc.
may, ail the sanie, show a striking resemblance with regard to the shape of the shell; i. e. that
in this range of forms the shape of the shell alone cannot be considered sufficient to characterize
a species.
It seems best, in order to avoid further confusion, to delete A. teres altogether from the
list of identifiable species, at least for the present. Only if a careful study of the Ostrocod fauna
at the type-locality, Oban, Firth of Lorne, Scotland, were to prove that only a single species
is forind liere with about the same type of shell as these forms would it be proper, to adopt this
species name of NORMAN’s again.
The form described by G. S. BRADY 1868 b, p. 465, under the name of Cylindroleberis
teres (Norman) shows a very striking resemblance to the species described by me above with
regard to the shape of its shell. — On the other hånd the resemblance to the species of
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