REPORT ON THE ANNELIDA. 
227 
lobe. The latter is broadly triangular, the upper and lower edges being also convex. 
The second lobe is double, since an unusually large process occurs in front of the bristles. 
The larger division is somewhat ovoid, with a blunt tip, which scarcely reaches that of 
the superior lobe. The double setigerous lobe beneath extends quite as far outward as 
the foregoing. The inferior lobe is lanceolate, the point falling short of the setigerous 
region above. The ventral cirrus proceeds a little beyond the middle of the latter lobe. 
Superiorly the bristles are all setose, with comparatively short tips (PL XVIa. fig. 17). 
The very fine spikes or setae on these are hardly seen under ordinary circumstances, 
except as a filmy margin. Similar bristles occur at the superior border of the inferior 
series. One or two falcate forms with elongated tips occur in the same group. The next 
division of the inferior series show's superiorly setose forms with shorter tips, and 
interiorly a number of falcate bristles with long spinose tips (PI. XVIa. fig. 18), some 
of which have an adnate wing just under the terminal hook. 
At the thirty- seventh foot (PL XXXV. fig. 12) all the lobes have become more acute. 
The dorsal cirrus is more prominent, and extends about half its length beyond the 
superior lobe. The latter nearly forms an isosceles triangle. The second lobe has its 
accessory superior process much diminished (in comparison with the tenth foot) ; its 
inferior margin is convex at the base, its tip is pointed, and does not reach as far outward 
as the superior lobe. The setigerous lobes are massive, broad at the base and acute at 
the tip. The inferior lobe does not reach as far outward as the latter. The ventral 
cirrus passes along two thirds nf the margin of the inferior lobe. 
In the intestine is muddy debris containing long sponge-spicules, fragments of 
Eadiolarians, a few Gregarinse (parasitic), fragments of Algae, often wuth groups of 
chlorophyll-granules, and many Diatoms. 
The nerve-cords in this form are arranged somewhat like those of Nereis pelagica, 
Linn., viz., above the attachment of the oblique muscles, and connected with the hypoderm 
by a median pedicle. They have thus externally the attachment and decussation of the 
oblique muscles, the thin circular fibres, hypoderm and cuticle. The ventral longitudinal 
muscles have a comparatively small pennate fold superiorly and externally. The 
perivisceral cavity contains large granular ova in the larger example dredged off 
Kerguelen in 10 to 100 fathoms. In these and allied forms a series of vertical fibres are 
found between the oblique muscles, passing up on each side of the nerve-cord to the wall 
of the alimentary canal, the fibres partly keeping to the same side, and partly crossing 
to the opposite. 
This appears to correspond with an imperfect specimen collected at Kerguelen by the 
“Antarctic” Expedition, and presented to the British Museum by the Admiralty, though 
no description by Dr. Baird has yet been found. It is allied to the Nereis (Lvcoris) 
masalacensis of Grube^ from Masalac in the Philippines. 
^ Aimel. Fauna d. Philippinen, p. 75, Taf. v. fig. 4. 
