448 
THE VOYAGE OF H.M.S. CHALLENGEE. 
Terebella {Lanice), tube only. 
Habitat. — Dredged at Station 76 (off the Azores), July 3, 1873; lat. 38° 11' N., 
long. 27° 9' W. ; depth, 900 fathoms; bottom temperature 40°'0, surface tempera- 
ture 70° ‘0 ; sea-bottom, Pteropod ooze. 
Only the tubes of this form were met with. These are a little longer than a crow- 
quill, and composed of the usual chitinous secretion strengthened by Globigermce and 
other Foraminifera, minute fragments of shells and mud. The extremity presents a 
remarkable expansion, having the outline of a spade or rather two spades (for the 
expansion is double), with a series of long filamentous processes projecting from 
the free margins. The flattened expansions have the same composition as the 
tube, and the jDrocesses consist of the usual secretion with fine sponge-spicules at 
intervals. 
This species is probably a Lanice, but nothing further can be said of it in the absence 
of the occupant., 
Terebella [Lanice) seticornis, n. sp., tube only (PI. XLIX. fig. 4). 
LLabitat. — Trawled at Station 322 (off the mouth of the Rio de la Plata, South 
America), February 26, 1876; lat. 35° 20' S., long. 53° 42' W. ; depth, 21 fathoms; 
surface temperature, 71°‘5 ; sea-bottom, sand and shells. 
This is a small tube (about 1‘5 mm. in diameter) attached to a group of Modiolarice, 
or rather both tube and mollusks are connected by the byssi. The chitinous wall of the 
tube is coated with rather large fragments of sea-worn shells. The aperture presents a 
ventral tongue-shaped flap, somewhat longer and narrower than in Lanice Jiabellum. 
The dorsal edge has a thickish pillar supporting the base of a fan split into a dozen 
primary filaments, which usually become bifurcate after a short course. The lobe and 
fan are composed of the ordinary tough secretion, in which grains of quartzose sand are 
neatly imbedded ; and as these are necessarily almost linear in arrangement in the 
filaments, a somewhat moniliform appearance is j>roduced. The attenuated tip of each 
filament is formed l)y a thread of the secretion strengthened here and there by spicules 
of sponges and bristles of Annelids. The extremity is occupied by a single long 
winged bristle with the tapering tip at the point, while another parallel with it a little 
lower down gives the region due stiflhess. Moreover, so transparent are many of the 
fragments in the filaments that the outlines of the Diatoms on their , surfaces, to which 
they are probably attached by the secretion, are quite distinct. 
