436 
THE VOYAGE OF H.M.S. CHALLENGER. 
of the somewhat truncate extremity of the body. In all there are about five segments in 
front of the anal styles. 
The ventral groove in the posterior region is pronounced, a feature partly due to the 
great muscularity of the lateral margins. The appearance, indeed, recalls that seen in 
the Opheliidse, and probably is dependent on the same structural cause. 
The three branchise have been lost, but they seem to have occuj)ied the usual 
position in Samytha. 
The dusky greyish mud in the intestine is by no means rich in organisms. Only a 
■few Diatoms and Eadiolarians, with fragments of sponge-spicules, are visible. 
The tubes are dark greyish, and friable externally, but internally have a tough 
translucent lining membrane. Microscopically even fewer organisms occur than in the 
contents of the alimentary canal. A large proportion of comparatively coarse grains of 
sand and fragments of sponge-spicules, with here and there a Diatom or the reticulated 
skeleton of a Eadiolarian, comprise the forms noted. 
The specimens unfortunately are not in a satisfactory state for minute investigation. 
On section the arrangement of the hypoderm agrees with that in the typical form, being 
thickest ventrally. The longitudinal ventral muscles are separated by a space as large as 
in Amphicteis. The oblique are powerful. 
VerrilD describes a new genus, Sarny thella, in which the bristle-bundles are fifteen 
pairs. 
Eusamytha, n. gen. 
Eusamytha pacijica, n. sp. (El. XLYIII. fig. 4 ; PI. XXVIIa. fig. 9). 
Habitat. — Trawled at Station 241 (in the Pacific, off Japan), June 23, 1875 ; lat. 
35° 41' N., long. 157° 42' E. ; depth, 2300 fathoms ; bottom temperature 35°‘l, surface 
temperature 69°’2 ; sea-bottom, red clay. 
A specimen measuring 33 mm. in length, with a diameter of 2'5 mm. at its widest 
part, anteriorly. 
This form seems to be intermediate between Samytha and Amage, having the six 
branchiae of the former, and the type of hooks approaching the latter. It differs from 
both in possessing fifteen pairs of bristles. 
The frontal margin is smooth and somewhat truncated anteriorly, and superiorly 
is also smooth, from the margin backward to the base of the branchiae, in front of 
which a transverse furrow occurs. Beneath the former lobe a dense series of some- 
what long tentacles overhangs the mouth, the adherent mass extending about two-thirds 
the length of the branchiae. The latter apparently spring as usual from the third 
1 Amer. Journ. Sci. and Arts, vol. v. p. 98. 
