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the greater part of their lengtli with close, fine, stift’, rather long hairs, arranged in shape
of feathers.
Sixth limb: — Forms a comparativelv short, lamelliform, very slightlv moveable
or sometimes immoveable, plate of somewhat varving type, situated ventrally on the body
between the mouth and the furca; is apparently never used as a locomotory organ.
S e v e n t h limb: — Originates rather high up on the side of the back of the body.
\ ery elongated and mobile, annelid-like, with very nunierous joint-like, ring-shaped chitinous
stripes (like the structure of the trachea), but with no real division into joints; flattened distally
and here armed more or less abundantlv with cleaniug bristles arranged in a single row along
the dorsal and ventral eriges of the limb. The cleaning bristles are of about the same
type within the whole group, rather powerful, annulated and provided distally with bell-shaped
segments, overlapping each other somewhat; these segments become more and more narrow
the more distally they are situated, and are armed along the distal edge with a dense series of
moderately long, fine, stift spines. This limb is often fitted at its point with teeth arranged
in the shape of a comb. It is absent in males of the genus Sarsiella.
Brush-like organ: — Is absent almost throughout. For the possible occurrence
of this organ on the penis see p. 76 above.
Co pula to ry organ: — Paired, varies a good deal in type; compared with
the same organ in other Ostracod groups it is in most cases of a rather simple structure.
The vasa deferentia do not pass through it.
F ur ca: — Always well developed, large, powerful, with comparativelv short, broad
lamelliform rami, always armed with several powerful claws. The posterior part of the dorsum
forms a rather strongly chitinized, oval, somewhat spoon-shaped furcal field, which is well
defined from the furcal lamellae and furnished with a well developed muscular system; see
({. \Yr. MÜLLER, 1894; pl. XXXV. figs. 5 and 11. Proximallv to the furcal claws there is no
unpaired bristle (such as is found for instance in Halocyprids and Polycop ids).
A 1 i m e n t a r y organs: — Mouth wide, narrowing rapidly towards the interior.
A t r i u m relativelv weakly defined. L a b r u m varving in type, sometimes very large,
sometimes rather small. L o w e r 1 i p very small, may bc quite absent. P a r a g n a t e s
most frequently quite absent, and if developed, small and weak. The glands of the
u p p e r 1 i p most frequently developed but very varving in type and development; may be
absent. Oesophagus rather long, most frequently very strongly muscular. somewhat
varying in type. S t o m a c h large, oval, most frequently without hepatical appendages;
surrounded by a layer of pigment cells, outside which is to be found a stratum of wide-meshed
connective tissue. R e c t u m very short, opening out in front of the furca. No parts of the
digestive organs ever penetrate between the lamellae of the shell.
Sexual organs: — Male: The testes are paired and consist of two
bag-shaped oval bodies situated posteriorly in the body. From each of the testes there runs a rather
short, wide canal, vas deferens; the vasa deferentia emerge with a common pore just
in front of the anus, i. e. between the two penes; they unite rather near the outer exit; see
C. W. MÜLLER, 1894, pl. XXXYJII. fig. 30. F e male: The ovaries, like the testes.
Zoolog, bidrag, Uppsala Suppl.-Ild, 1
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