220 
THE VOYAGE OF H.M.S, CHALLENGEE. 
only a narrow line occurring along the ventral border. The posterior pair lie 
immediately behind the foregoing, and have the much smaller and somewhat ovoid lens 
directed outward and backward, the great mass of the pigment being anterior and 
internal, though a much broader margin of pigment occurs externally than in the case of 
the anterior pair. The paljDi are of average size. 
The buccal segment is somewhat’ broader than the succeeding, and has the anterior 
margin on the dorsum only very slightly curved forward. The l^asal region of the 
proboscis shows dorsally a single prominent elevation bearing a pair of large brown teeth 
(V.), and a smaller one below them (in extrusion). The basal circular series (VII. and 
VIII.) is in three ranks, a considerable interval on each side occurring between it and the 
former. When the proboscis is extruded these form a sparsely armed region, the larger 
teeth being distal and the smaller proximal. On the dorsal surface of the maxillary ring, 
at the base of the maxillae, are three groups — a median (I.) consisting of a single rather 
large tooth, and a small grouj) (II.) on each side of from five to seven teeth, all of which 
(with the excejjtion of the first) are smaller than those of the basal series of three rows. 
Three groups occur interiorly in the same region, a median (HI.), consisting of a central 
and eight surrounding teeth, and two lateral (IV.) each more than twice the size of the 
superior groups. The maxillae are dark brown from the tip almost to the base, and in 
the only one available for examination four teeth are present below the terminal 
fang. 
There is no marked change in regard to the structure of the foot in front. The tenth 
foot (PI. XXXV, fig, 2) presents dorsally a slightly arched base, from the outer slope of 
which a rather short dorsal cirrus proceeds. About a fourth of it extends beyond the 
tip of the dorsal lobe. The latter is broad at the base, has a somewhat regular incurvation 
on its superior and inferior margins, and ends in a peculiarly truncated tip. The next 
region has a similar extremity, but its base is convex interiorly. It extends outward nearly 
as far as the superior lobe. The inferior setigerous division is considerably produced, and 
has a well-marked terminal process on each side. The inferior lobe is large, similar to 
the second in shape, and reaches nearly as far outward as the setigerous division. The 
ventral cirrus extends little further than the middle of this lobe. The superior bristles 
are setose, and the inferior setose and falcate. 
At the thirty-seventh foot an elevated process occurs internal to the base of the 
dorsal cirrus, which hardly reaches the tip of the elongated and somewhat conical dorsal 
lobe. The second region is gibbous at the base, and extends fully as far outward as the 
first. The inferior setigerous division is long, though the great increase in the two 
upper render this feature less conspicuous. A well-marked collar exists a little within 
the terminal papillae. The ventral lobe is also very long and lanceolate. The ventral 
cirrus has the same proportional length, but now springs from an elevated process which 
bulges beyond its base dorsally and ventrally. 
