REPORT ON THE ANNELIDA. 
175 
Alciopa, Milne-Edwards. 
Alciopa antarctica, n. sp. (PL XXVIII. figs. 2, 3, 4 ; PI. XXXII. fig. 12). 
Habitat. — Procured along with Cleoclora on the surface of the Antarctic Sea, 
February 21, 1874, between Stations 154 and 155 ; surface temperature, 32°‘0. 
A large form, measuring about 73 mm. in length, and at its widest portion stretching 
about 18 mm. from tip to tip of the bristles. 
The body is curiously barred with brown, the intermediate pale ]3ortions of the anterior 
third affording a very bold contrast. The pigment is somewhat irregularly arranged 
in front, a long dark brown region stretching from the head to the tenth segment, 
then two narrower brown belts with intervening pale portions occur, these being followed 
by various lateral patches. Posteriorly a dark belt runs from the foot upward over 
the dorsum on each side, and is lost for the most part before reaching the median 
line. On the ventral surface the anterior long dark region is continued from the head 
backward as on the dorsum, and the two succeeding brownish belts follow a similar 
arrangement. Pigment-patches proceed from the feet inward, but not so far propor- 
tionally as on the dorsum. The body is conspicuously rounded on the dorsum, less so 
ventrally. It tapers much more anteriorly than posteriorly, but the latter is imperfect. 
The neck is extremely narrow, so that the head, with the large eyes, is prominent all 
round. A very narrow portion, again, occurs about the middle of the first or long brown 
region. 
The head recalls that of the dragon-fly, the halves being almost wholly formed by the 
great eyes. Dorsally these are of the same brownish colour as the rest of the dorsum. 
Posteriorly a kind of bridge between them causes an elevation in this region. In front 
of the latter is a hollow, from which a short median tentacle springs. A whitish eleva- 
tion occurs a little in front, its anterior edge being furnished with three small lobes. On 
each side of it in front is a short antenna, and another pair spring from its anterior edge. 
The latter elevation and processes are at the anterior border of the cephalic region. The 
corneal region of the eyes is invisible from the dorsum. On turning to the ventral 
surface twm well-defined cornese occur, each occupying the centre of the great browmish 
ocular area on each side, and separated by a deep fissure in the middle line. Toward its 
outer border the corneal area shows a dense whitish lens. The corneal surfaces just 
mentioned are not horizontal, but bevelled, so that they look outww’d as well as 
downward. Moreover, the cornese are close to the ventral border (or tip) in front of the 
mouth. This buccal frill has a somewhat short and thickish cirrus on each side, opposite 
the outer border of the cornea. A longer cirrus occurs on each side of the two succeed- 
ing segments. 
