ETHONE DEPRESSA. 429 
It tapers a little toward the snout, and more gradually toward the tail, which ends in two 
spathulate cirri. Foot with an ovato-rotundate dorsal lamella with a short cirrophore. 
Setigerous process bluntly conical, the tip bemg double (with a bite in the middle), 
supported by a pale spine. Bristles translucent, shaft with a distal curvature, its 
convexity directed upward; terminal piece slightly larger than in KHteone picta, and 
forms a translucent, tapering, serrated blade. The shaft above the dilatation carries a 
long, tapering spur curving toward the serrated edge of the blade. Ventral cirrus 
anteriorly a truncated cone. 
SYNONYMS. 
1865. Hteone depressa, Malmgren. Nord. Annul., p. 103, Tab. xv, fig. 36. 
HBIS, 9g Pe Théel. Annel. N. Zembla, p. 32, pl. ui, figs. 19 and 20. 
1883, F ? Levinsen. Vid. Meddel. nat. Forhandl. Copenhagen, p. 208. 
NONI’ 3 eS Fauvel. Annel. Arctique, p. 27, pl. 1, fig. 6. 
GUD 8s eee Ae McIntosh. Ann. Nat. Hist., ser. 8, vol. x, p. 119, pl. v, figs. 1—5. 
Habitat.— Between tide-marks at Scarborough (Irving and Arnold Watson). 
Abroad it has occurred at Bellsund and Whalers’ Point, Spitzbergen (Malmgren) ; 
Greenland (Préven) ; Nova Zembla (Théel) ; Murman Sea (Fauvel) ? 
The head (Plate CX XXIV, fig. 1) is somewhat conical, with a smoothly rounded anterior 
border, from the sides of which spring the four subulate tentacles, which taper distally and are 
nearly equal in length. Behind these the snout is constricted, then gradually widens till near 
the posterior border, when a slight constriction again occurs, thus giving a characteristic outline 
to the prostomium, the posterior border of which is carried backward in the middle line. 
Just in front of the central point is a minute boss, the presence of which at once attracted 
Mr. Watson’s attention, and which, though in a different position, simulates the unpaired 
tentacle of Hulalia. On each side and a little in front of the boss is a comparatively small 
eye, quite distinct at first, but which gradually faded in the preservative fluid, as, deed, 
happens to other species of the genus. The peristomium bears two tentacular cirri of 
similar shape to the tentacles and scarcely longer. 
The body is about 34 inches long and about ;'; of an inch wide (Watson) in life, and it 
is flattened both dorsally and ventrally, the latter surface being distinguished by a broad 
median depressed band and a short lateral area in each segment. On the dorsum, again, 
a similar effect is produced by the slight elevations at the outer border of each segment, 
though the median section is slightly convex and of the colour formerly mentioned. It 
tapers a little toward the snout, and much more gradually toward the tail, which ends in two 
lobate or spathulate cirri (Plate CX XXIV, fig. 2). The segments throughout are well marked, 
and in the preservative fluid (2} per cent. formalin in sea-water and then alcohol) a curious 
increase of the pigment has occurred, with pale segment-junctions. The dorsal and the 
ventral cirri are dark like the ventral surface, but the setigerous processes remain pale; such 
of course, though interesting, is the effect of the preservative fluid, and must not be con- 
founded with its original pallor. The colour when alive was whitish or cream-coloured, 
but in sea-water with 24 per cent. of formalin it passed through lemon-yellow to a dark 
brown, the tints being darker in some parts than in others, whilst a few points remained 
cream-coloured. 
