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Philomedes Lilljeborgi. G. O. Sars. 18S6. p. 74.
A. M. Norman. 1891. pp. 119, 121.
G. S. Brada and A. M. Norman. 1896. p. 6.78. pi. LL. figs. 4 to
6; pi. LII. figs. 3. 4.
H. H. Gran. 1902, pp. 20, 66. 80. 210.
P. T. Cleye, 1903, p. 24.
C. H. Ostenfeld, 1906, p. 97.
.. .. .. and C. Weseneerg-Llnd. 1909. p. 114.
,. .. APSTE1N. 1911. p. 169. pi. XXIII. fig. 4.
Description: — Female: —
Shell: — Leneth 2.15—2.6 mm. It does not seem to be decidedlv larger in northern
than in Southern locales; a few specimens from Lofoten that I had an opportunitv of
investig-ating had shells about 2,3 mm. long, whieh was the average length of the specimens from
Skager Rak that were investigated by me. Length : height. about 1.45 : 1; length : breadth.
about 1,8:1. Seen from the side (fig. 1) it is „rounded-sub-quadrangular“, with
its greatest height at about the middle. The dorsal margin is onlv weakly arched. sometimes
almost straight. running almost parallel with the longitudinal axis of the shell, and with broa div
rounded corners passing into the rather steeply descending anterior and posterior margins.
The ventral margin is uniformlv and moderately eurved and weakly pouting just behind the
rostral incisur. The posterior part of the shells forms, somewhat ventrally of half the height
of the shell, a rather small but eharacteristic beak — which is perhaps the easiest means of
distinguishing this species from Ph. (Ph.) globosa. Above this beak-like process the
posterior margin of the shell is straight or verv slightlv arched. The rostrum has in most cases
a rather pointed anterior corner, which projects almost at right angles; its ventral corner is
rather pointed and is armed with a small spine-like process. The rostral incisur is rather deep
and narrow, defined from the ventral margin of the shell by a slight protubérance. Seen
from b en ea t h the shell is oval with its greatest breadth at about the middle; the
anterior and posterior extremities are almost similar, the side contours are uniformly eurved
(agreeing fairly well with pl. LII, fig. 4. G. S. BRADA and A. M. XORMAN, 1896). The s u
r-f a c e of the shell is smooth. without any marked protubérances exeept the little spine
on the ventral corner of the rostrum and a very slight ridge behind the rostral incisur, running
out on the little protubérance, which. as has been mentioned a bove, marks off the rostral incisur
from the ventral margin of the shell. It has onlv some scattered and moderately long bristles;
these bristles are characterized by coming to a fine point from a rather broad basal part — they
are of about the sanie type as the long bristle in fig. 4 of Ph. (Ph.) globosa. The pores of the
surface are of moderate size. rather numerous and often very difficult to observe with certainty.
Seen from inside (figs. 2 and 3): Medial bristles: The row of bristles on the rostrum
consists of a rather large nurnber of bristles, about as in fig. 2. On the posterior portion of the
list there is a moderate number of bristles, partly arranged in small groups. On the part of the
shell between this part of the list and the margin of the shell there are a few very short bristles.
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