198 
THE VOYAGE OF H.M.S. CHALLENGEK. 
The setigerous region of the foot (PL XXXIV. fig. 2) is bilobed, and furnished 
superiorly with three spines, which do not project beyond the surface, and inferiorly 
with a group of stout bristles (PI. XXIXa. fig. 14), having somewhat short distal append- 
ages. The anterior edge of each of the latter presents one or two serrations, besides the 
well-marked bifid tip, which resembles that in Eiisyllis. The ventral lamella is lanceolate 
or ovato-lanceolate, the tip projecting about as far as that of the setigerous region. 
This species differs from Syllis hrasiliensis in the shape of the palpi, the arrange- 
ment of the eyes, in having the distal ends of the shafts of the bristles less abruptly 
dilated, and in the more elongated bifid appendages. By the former character it is 
easily distinguished from Eusyllis tvbifex, Gosse, the bristles of which are closely allied. 
Syllis ramosa, MTntosh (PL XXXI. fig. 1; PL XXXIII. figs. 11, 12, 13, 14; 
PL XVa. figs. 18, 19 ; PL XVIa. fig. 1 ; PL XXXIVa. figs. 8, 9, 10, 12, 13). 
Syllis ramosa, M‘I., Journ. Linn. Soc. Lond. (ZooL), vol. xiv. p. 720, 1879. 
Habitat. — Trawled at Station 192 (off Tionfolokker Islands in the Arafura Sea), 
September 26, 1874; lat. 5° 49' 15" S., long. 132° 14' 15" E. ; depth, 140 fathoms; 
surface temperature, 82°'0 ; sea-bottom, blue mud. Also at Station 209 (near Zebu, 
Philippines), January 22, 1875 ; lat. 10° 14' N., long. 123° 54' E.; depth, 95 fathoms: 
bottom temperature 71°, surface temperature 81° ; sea-bottom, blue mud. 
In both instances the ground was peculiarly rich in Ewplectella and other 
Hexactinellid Sponges and Sipunculi, the canals of the former, especially just above the 
“wisp,” being occupied by this remarkable Annelid in great numbers. It was not 
observed in life. Besides the Syllis, the sponge in one instance was tenanted by Polynoe 
hexactinellidcB. 
The Syllidian [Syllis ramosa) is located for the most part in the basal canals of the 
sponge, above the wisp. In this region masses of the Annelid, about a quarter of au 
inch in diameter, occur, and a multitude of branches pass into the smaller canals 
adjoining. Two of such masses are especially conspicuous. The intricate manner in 
which the branches are arranged makes it a very difficult matter to dissect them out, 
especially when the friability of the Annelid and the sharp spicules of the sponge are 
taken into account. Even after removal from the sponge it is a laborious operation to 
unravel them without frequent rupture. 
The masses and their numerous branches, as well as the isolated portions, consist of a 
Syllis-Yiko- Annelid of the thickness of common sewing-thread. In the specimen within a 
sponge from Zebu, which was first sent me, no head can be observed either in the parent- 
stock, amongst the masses, or in the canals elsewhere, so that they must either be very 
few, only occasionally developed, or by some means have been swept off, as it is hard to 
