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medes and Asterope. It appears to me that there is a support for this assumption
in the folio wing facts:
That the endite on the coxale of the mandible was originally bifurcated in the
Cy-pridiniformes seems to be supported by the fact that bifurcation is found not only in the
sub-family Philomedinae and the Asteropids but also in Cypridininae and Sarsiellidae.
Moreover, in the sub-family Cypridininae the bifurcation of this process is best developed
in that genus which we have rather good reasons to assume as the most primitive, viz.
Crossophorus, cf. below, p. 182. In most species of the family Sarsiellidae this process seems
to be absent, but when it does occur it is deeply bifurcated. at least according to G. S.
BRADY and A. M. NORMAN, 1896, PL LX, fig. 10. This endite is not developed, so far as
is known, in Rutidermatidae. — I must not refrain, however, from stating that there are
facts that might be considered to point in the opposite direction; cf. below p. 182. — The
supposition that the basale of the mandible in Cypridiniformes originally had an endite
is supported by the fact that an endite on this joint occurs in Halocypriformes,
Polycopi-formes and Asteropidae, and traces of one in Philomedinae, Cypridininae, Sarsiellklae and
Rutidermatidae; in the Cyridinenes the traces are best developed in the genus
Crossophorus, which was pointed out above as being presuniably the most primitive type of
this sub-family.
The occurrence of glandular helds on the u p p e r 1 i p in both Cypridininae,
Philomedinae and Asteropidae seems, of course, to support an assumption of the primitiveness
of this character.
With regard to the eventual primitiveness of the selvage of the shell in
the Philomedines and Asteropids I content myself with referring to what
has been stated above.
Other characters in Philomedes could be brought forward, in which this genus agrees more
closely with the A s t e r o p i d s than does the sub-family Cypridininae. Among these the
following may be mentioned:
The first antenna: The second joint always has a distal-lateral bristle; the
posterior edge of the original fifth joint is in the male so much shortened that the sensory
bristle of this joint seems most frequently to be placed next to the posterior-distal bristles
of the fourth joint. In the males the bristles of the distal joints are always without suctorial
organs; the c- and f-bristles (cf. the terminology for the sub-family Philomedinae) are very
much lengthened in this sex.
The second antenna: The endopodite is always developed as a clasping organ
in the males.
The penis is always of about the same type, small with weak musculation, more
or less clearly bifurcated distallv.
It is, however, to be noted that at least some of these characters may be considered old.
presuniably belonging to the ancestral forms of Cypridinif ormes. Such characters are: the
absence of suctorial organs on the first antenna in the male, the dev.elopment of the endopodite
of the second antenna as a clasping organ in the male (we find both these characters in the
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