- Project Runeberg -  Zoologiska Bidrag från Uppsala / Suppl.-b. I. 1920. Studies on marine ostracods, p. I /
478

(1911-1967)
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hyaline spine. At about half way between and parallel to the posterior margin of the shell
and the dorsal half of the spine-bearing list there is a sparse row of about six or seven
broad pores; each pore is furnished with a freely projecting hyaline peg (the shape of these
pegs could not be observed with certainty). Behind the dorsal half of the posterior medial
row of bristles is seen in fig. 3 a double line running transversely over the shell; this
corresponds to a sharp edge. The part between this and the posterior margin of the shell
is situated rather considerably more laterally and thus, when it is looked at through the
microscope from inside, rather considerably deeper than the part situated within the double
line. This character is in most cases only distinctly developed on the right valve, as on
the left valve this ridge is so near the margin of the shell that it often seems quite to
coincide with the latter.

First antenna (fig. 4): — This has seven joints, the third and fourth joints are
free from each other. These two joints together form a joint that is somewhat shorter than it
is high and also somewhat shorter than the total length of the fifth and sixth joints. The distal
boundary of the fourth joint is rather strongly concave. The anterior bristle of the second joint is
somewhat longer than the anterior side of this joint. The third joint has six anterior bristles,
of which nos. 5 and 6 are fixed at the side of one another. Nos. 1, 2 and 4 of these bristles are
armed ventrally with long, sti ff secondary bristles, the others have short hairs. The longer
of the two posterior distal bristles on the fourth joint is not quite as long as the the fifth joint.
Sensory bristle of the fifth joint: The stem is about as long as the total length of the third to
the fifth joints; it is furnished with seven sensorial filaments. The end joint has seven bristles,
the d-bristle is developed as in the preceding species but unlike all the other species of this genus
in which this character is known. The a-claw is somewhat longer than the total length of the
anterior side of the two next distal joints and is exceedinglv finely and weakly pectinated
proximo-anteriorly. The f-bristle has four or five sensorial filaments. The c- and g-bristles have a
some-what varying number of sensorial filaments: on the type-specimen the c-bristle had nine, the
g-bristle seven on the antenna of the right side; on the antenna of the left side the c-bristle
had seven, the g-bristle eight filaments; on two other specimens botli these bristles had seven
sensorial filaments on both the right and the left antennae. The d-bristle is somewhat more
siender but rather slightly shorter than the e-bristle. Pilosi ty: The first and second joints have
numerous groups of stiff, fine hairs on the greater part of both the inside and the outside (not
drawn in the figure); there never seem, however, to be any such bristles on the anterior distal
part of the inside of the second joint. Distally the second joint has a close row of short, stiff
hairs antero-laterally.

Second antenna: — Distally on the inside close to the exopodite the p r o t
o-p o d i t e has one very short bristle. The exopodite has four bristles on the end joint;
the fourth to the ninth joints of this branch have basal spines. The endopodite is distinctly
three-jointed; its end bristle is about as long as the stem (fig. 5).

Man dible: — Protopodite: Coxale: The scythe-shaped process (fig. 8) :

The part situated distally of the main spine grows uniformly and gently narrower in a fine point;
its ventral edge is even, almost straight or even slightly concave. The distance from the point

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