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to it; it may very well be considérée! as an accessory appendage. Neither the position, size nor
structure of this process form any decided argument in favour of its being a brandi. The
position is explained by its funetion; it is an organ for breaking up food or carrying it to the
inouth or towards the masticatory appendages that are situated in front; the distal endite on
the maxilla has about the same position. The size is of very little value as an argument ; in this
connection it will be enough to point out that the endites on the maxilla are often of considérable
length, sometimes almost as long as the palp that has been explained as an endopodite. The
structure seems to be an argument against, rather than for, its having the nature of a brandi;
it is always unjointed, in most cases not even bounded proximally; (a proximal boundary need
not, as a matter of faet, have much significance, as I have myself observed specimens of a species
belonging to the genus Macrocypris in whieh the middle one of the three endites of the maxilla
had a well-defined proximal boundary); finally it is practically always without muscles inside
itself — contrary to the backward pointing branch; 1 only succeeded in observing these muscles
in the Halocyprids; cf. below, however, for the latter characters.
This investigator does not bring forward any other reasons for his view.
It ought to be clear from this that G. W. MÜLLER has not proved in any decisive way
the assumption put forward by him as to the morphological nature of the vibratory plate on
the three posterior limbs.
On the other hånd we find that none of the investigators who adopt the view that the
vibratory plate on the posterior limbs is of the nature of an exopodite has advanced anv decisive
proof for his view. The only one who has made a serious attempt to support his assumption
by facts is G. Alm. This investigator has advanced a number of facts which seemed to him
to support the idea that the forward pointing process on the fifth limb of a number of C y p r i d s
and of C y ther el la has the nature of a branch. We read in this writer’s work of 1915,
pp. 9—10: „Diese Bildung entspricht doch was Form und Lage anbelangt den Kauladen am
Mandibel und der Maxille, zumal sie auch an der Innenseite des Beines sitzt, was nicht für den
Exopodit gelten dürfte, und weiter vermißt man vollkommen etwaige Muskeln in derselben,
was alles gegen die Deutung als Exopodit sprechen muß.“
I have tried to show above that the shape and position of this process cannot be used
as proofs of its having the nature of a branch, but these characters are equally incapable of
being used as evidence in favour of the opposite opinion. The position is distal on the protopodite,
i. e. where one would expect to find it if it were a branch. It is true that it is always unjointed,
but in connection with this it may be pointed out that the same thing is always true of the
exopodite on the mandible, of which no investigator has yet denied that it has the nature of
a branch. With regard to G. Alm’s argument that this process has no muscles it may be pointed
out, first, that these can be observed in the H alocyprids (cf. fig. 27 of Conclioecia
symmetrica G. W. Müller, in this treatise), secondly that muscles are also absent in the exopodite
of the mandible of Cypridinidae, etc. G. Alm assumes in the same work, p. 10, that the strong
development and individualization of the forward pointing process on the fifth limb of
Macro-cypris is connected with the faet that this limb is in this genus also used as a crawling leg and
a climbing organ and in conséquence of this „nicht so weit nach vorne verschoben werden kann.
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