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like to start out from it in judging G. W. MüLLER’s view in this case. The latter vvriter assumes
that in C y p r i d s, D a r w i n u 1 i d s, N e s i d e i d s and C y t h e r i d s the distal
proto-podite joint has been quite lost. But where is the proof of this assumption? As far as I can see
there is none. G. W. MULLER brings forward in this connection the faet that in the genus
Cythe-rella the bending into a knee takes place between the first and second protopodite joints. But
this does not prove this assumption. The faet that this formation of a knee in the second antenna
in the Ostracods has actually taken place at di fierent places — between the pro topodite on the
one hånd and the exopodite and endopodite on the other in C y p r i d i n i d s, H a 1 o c y p r i d s
and Polycopids and between two pro topodite joints in Cytherella — may at least be
explained by assuming that this limb of the Protostracods was of so primitive a
type that no definite formation of a knee had as yet taken place. This assumption seems to
be supported by the faet that this limb differs very mueh in its type in the different Ostracod
groups. The genus Cytherella is comparatively far removed- from all other Ostracods by its
whole organization (G. 0. SARS as we know distinguished this genus as a special group, parallel
to Myodocopa, Podocopa, etc.). The ancestors of this genus presumably branched off from all the
other Ostracods at a rather early period. Perhaps this differentiation even took place so
early that the second antenna had not yet acquired a definite knee. At any rate this possibility
must be regarded as being present. G. W. MüLLER’s view finds just as little to support it in
embryology as in comparative morphology. I have never found any trace of the distal
proto-podite joint which, according to G. W. MÜLLER, has disappeared in larvae of C y p r i d s
or other forms in which, according to this author, it is absent in the mature specimens.
Nor has G. W. MÜLLER or any other investigator of this problem ever mentioned
such a trace.
Moreover, according to G. W. MüLLER’s assumption, in the forms whose distal
proto-podite joint has disappeared the place on the body from which this antenna issues has developed
into a joint-like process. What has caused G. W. MULLER to assume that this process, which
resembles a joint very mueh by its type, lias not been a part of this antenna from the very
beginning? We are given no information at all as to this; I should like once more to quote from
the above-mentioned work of W. GlESBRECHT. This author writes as follows with regard to the
réduction of the basal joints of the maxillipeds that is assumed by C. CLAUS for the Copepoda
(p. 86): „Wie ist dieser Verlust namentlich für den hinteren Maxillipeden zu begreifen, der doch
durch seine Länge und die hohe Zahl (7) seiner Glieder bei den meisten der höher stehenden
Copepoden zeigt, daß er eher einer Vermehrung als einer Verminderung seiner Gliederzahl
bedurfte, als seine Function im Herbeischaffen von Nahrung zu bestehen begann?“ One
must necessarily follow W. GlESBRECHT in trying to find out the reason for such a
réduction in the number of joints. Why, one asks, has this limb, which needs to
be relatively long in order to fulfil its supposed function as a locomotory organ, first
reduced its lengtli by the total disappearance of the second protopodite joint, and then (or
at the same time?) made up for this loss in length by the development of an accessory process
that does not belong to the original limb. Such a question as this may perhaps seem unscientific,
but it seems to be forced inevitably on the reader’s attention.
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