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First antenna: — This issues high up on the forehead. There are never more
than six clearly distinct joints. In other respects its type varies considerably.
Second antenna: — The protopodite, which is situated by the side
of the upper lip, issues from a rather narrow base and is very moveably joined to the body. It
is large, relatively high, pear-shaped, in most cases somewhat more elongated than in the
Cypridiniformes, somewhat flattened at the sides, with very powerful musculature, unjointed,
without any evident traces of the boundary between the original joints and always without
bristles*. Exop odite: This is very moveablv joined to the protopodite, with which, when
at rest, it forms a distinct ventrally open knee. It is developed into a powerful, elongated,
(always?) nine-jointed locomotory organ, used in swimming. (All the species of this group
that were investigated by me had constantly nine joints, but, according to G. W. Müller,
this branch has only eight joints in the genus Thaumatocypris; cf. the remark on this sub-family
on p. 580 below.) Its first joint is always elongated and in most cases of about equal thickness
along its whole length; most frequently it does not form disto-laterally a ratchet of the type
characteristic for the Cypridinif ormes. This joint is never armed vvith long natatory bristles.
The eight following joints, of which the seven distal ones at least are short, become more and more
narrow the more distally they are situated; the one next to the distal one is sometimes very
small, even rather difficult to observe. Each of these eight joints are furnished disto-ventrally,
somewhat medially, with a long and powerful natatory bristle. These bristles are annulated
along the greater part of their length and are armed — also along the greater part of their length
— with moderately broad natatory hairs, arranged in the shape of a feather. The end
joint has a somewhat larger number (two or three were observed) of bristles; the ventral one of
these is always a long natatory bristle, but usually somewhat shorter and weaker than those on
the preceding joints; the other (or the others) are somewhat (more or less) shorter and weaker
than the ventral one. All the bristles on this branch are without spines. Along the distal edge
of a larger or smaller number of the second to the eight joints there is often a series of more
or less weak spines; as I found this character varying rather considerably, I thought it best
not to include it in the following descriptions. Basal spines in the sense in which this term is
used by me in the group Cypridinif ormes always seem to be absent in the Halocypriformes.
The endopodite is always shorter than the exopodite, but is always well developed. It
has never more than three joints; otherwise it varies in type. It is used only in exceptional
cases as a locomotory (natatory) organ.
Manclible: — This is always powerful and elongated, and is chiefly used for holding
the food fast and for mastication (also a climbing organ?). Protopodite: This is always
two-jointed. The coxale, which is fixed obliquely forwards and downwards on the side of the
body just behind the second antenna, is very powerful, strongly chitinized and very short and
high; it consists of a rather narrow wedge-shaped dorsal insertion part, which forms the place
of attachment for a number of very powerful muscles, and a particularly powerful ventral
* J. IJ. Dana (1852, pi. XC, figs. 4 b and 5 b and pi. XCI, fig. 8 e) draws a bristle distally on the protopodite
of Conchoecia and Halocypris. In addition G. S. Bram y (1880, pi. XL, fig. 7) draws two long bristles at about the
middle of the protopodite of ..Halocypris atlantica Lubb“ (presutnably = Conchoecia serrulala C. Claus). This is certainly
due to mistakes on the part of these writers.
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