110 
THE VOYAGE OF H.M.S. CHALLENGER. 
greatest breadth 2 mm. If the bristles be included in the latter then it is nearly 
8 mm., so long are the feet and these organs. 
This form somewhat approaches Macellicepliala mirabilis, from Station 269. The 
body is narrow and elongate, delicate and semi-translucent in the preparation, and with 
very long feet and bristles. The proboscis and intestine are quite visible from the 
exterior; and posteriorly large nucleated cells are observed in the upper lateral regions. 
The mouth forms a well-marked aperture surrounded by puckered edges on the under 
surface of the buccal segment. The anus is terminal and prominent. A cirrus is 
probably attached to a small papilla on each side (between the anus and the large cirrus). 
The head is rather rounded, with a pale elevation on each side of the tentacle, as if 
from a large pale eye. The large whitish opacity in the middle of each may represent 
ocular pigment. The origin of the tentacle is peculiar, being nearly in the middle of the 
head. It is elongate and filiform, gently taj^ered from base to apex. A pair of very 
minute filaments (one in front of each eye) may represent antennae. The organs 
apparently corresponding to the palpi are considerably shorter than the tentacle, have a 
somewhat falciform outline, with a tapering tip. The tentacular cirri have the same 
shape as the tentacle, and appear slightly jointed under a lens, perhaps from imperfect 
preservation. The dorsal cirri are l^orne on the feet at a considerable distance from the 
body, and their slender tips project beyond the most prominent bristles. The last pair 
present in the preparation (only a papilla without a ventral cirrus intervening between 
each, and the anus) are much larger than the others, and appear to be articulated at 
the base. The ventral cirrus is a simple tapering slender process. All these organs are 
smooth. The ventral papilla forms only an elevation. 
The scales seem to amount to nine pairs, and are all comparatively small and semi- 
translucent. The first pair occur on the first feet, and are so small as to form little 
round lamellae, about the diameter of the feet. They are supported on a pedicle. The next 
two pairs occur as usual on the third and fourth pairs of feet, and are gradationally larger. 
The succeeding scales are on alternate feet, and three are nearly equal in size. Thereafter 
they diminish toward the tail, the last (on the terminal foot), however, being larger than the 
first. All are pedicled. The scales are delicate, translucent smooth structures with an 
opaque patch over the pedicle, from which a series of bifurcating nerves radiate to the 
margin. From their position the scales project more over the bases of the feet than over 
the dorsum, and in the majority they do not touch each other on the same side, and are 
separated by a wide interval from their fellows of the opposite side. In shape the larger 
have the antero-posterior diameter longer than the transverse. 
When viewed from. above the feet are elongate, an enlargement occurring just within 
the tapering tip. Viewed antero-posteriorly, the foot presents an outline not unlike that 
in the Ilesionidse, at least in the shape of the distal part. Toward the base dorsally is 
