314 : MYXICOLA INFUNDIBULUM. 
Sabellid in the absence of a collar, for the first seement is smoothly rounded on each side to 
the base of the branchial fans, whilst ventrally a triangular process passes forward in the 
middle line below the division between the branchial fans, and dorsally a slight projection 
also points between the fans from the anterior end of the groove. Montagu describes the 
mouth as purple, whilst the lips are bordered with chestnut. Dalyell found no tentacles 
Malmeren’s tentacles refer to the frilled processes on each side of the mouth. 
The branchial fans appear to cling more tenaciously to their bases than in ordinary 
Sabellids, and comparatively few of the preparations are devoid of them. ‘The filaments 
range from twenty-one in each fan (Shetland) to thirty-seven (South Devon), and they are 
connected by a web (which Claparéde states is ciliated externally) almost to the tip, as in 
Chone. In structure each filament agrees in the main with that in Sabella, the camerated 
chordoid axis passing along its entire length and a slender continuation of it reaches to the tip 
of the terminal process, which has a tapering web on each side, and is often deeply tinted 
purple. The pinne are comparatively long and likewise have a chordoid axis (not distinctly 
camerated), and they taper a little from base to apex. Toward the tip of the filament the 
rows of pinnee terminate in a double series of papillee, which, like the pinne, are alternate. 
The branchial plumes are of a rich dark chocolate brown in life, the brown being chiefly 
confined to the filament externally, and the pinnee, which are capable of independent 
motion, are of a rich purplish red. The bases externally, however, are of the colour of the 
body, viz., a dull orange. The two branchial fans are often separated to their bases during 
the movements of the animal. Montagu describes them as singularly beautiful and of a 
purple colour, darkest at the tips of the rays, and the pinne of a chestnut colour shaded to 
purple near the centre. In the Zetlandic specimens, 2 or 24 inches long, the body had the 
diameter of an ordinary goose-quill, the branchial fan measured about half an inch antero- 
posteriorly, but when the fans were flatly extended laterally their diameter was about an inch. 
The body (Plate CXIV, fig. 4) in the preparations is somewhat fusiform, for, besides 
the distinct tapering posteriorly, it is narrowed in front, and in life it sometimes assumes 
the same outline. It is rounded throughout except anteriorly, where on the dorsal surface 
a etoove passes backward in the middle line to the eighth segment, which it cuts obliquely 
as it goes to the right, and ends ventrally about the middle of the ninth. - In some, traces 
of the median groove are found behind the slope to the right in the eighth segment. It 
is of a dull orange hue throughout or in some pale, though in the Zetlandic specimens a distinct 
white ring encircled the body in front of the third segment-junction. Montagu mentions 
that the body is “ of an orange-colour annulated with whitish.” The number of segments 
varies, for Montagu gives the large southern form of 8 or 10 inches in length no less than 
150 or 160 segments, whereas the smaller Zetlandic examples (of 2 or 24 inches) had but 
45—52.1 The segments are distinct, but little differentiated dorsally and ventrally, and 
therein differing from the ordinary Sabellids, but they often show one or more rings— 
especially one ventrally near the posterior border—and in some examples a slight peak 
occurs at the posterior border of each near the posterior third. The segments become 
narrow at the tapering posterior end and terminate in a median anus at the somewhat 
blunt tip. 
The vascular system contains greenish blood and is similar in arrangement to that of 
1 In small examples the anterior region may have fewer segments. 
