Dr. Johnston on British Annelides. 7 
The mouth is inferior, and so concealed that it can be seen only 
from the ventral aspect. The wide undefined orifice is surrounded 
by a thick lip, the upper lip being formed of two comparatively 
large egg-shaped tubercles (fig. 2) ; and within the under lip 
there are two processes like palpi. From the external side of the 
anterior tubercles there arises, on each side, a ¢tentacular cirrus 
(figs. 1,25), similar to the tentacula in all respects, and projected 
in the same direction, but only one-third of their length. 
The proboscis is armed with several small dark corneous Jaws, 
denticulated on the inner side, and arranged in two rows, in the 
same way as in the genus Hunice. See Aud. and Edw. Litt. de 
la France, pl. 3. fig. 11. 
_ The occipital segment has no appendages. The segment behind 
is nearly of the same size, but those which follow are narrower, 
the length bemg about one-third of the transverse diameter. 
Above and below the foot there is a cirrus (tig. 3). On the an- 
terior segments the superior cirrus does not project beyond the 
foot, but it becomes considerably longer on the posterior, and is 
simple on all of them, with a joint at the base. The foot is 
formed of a tubercle and sheath, armed with bristles collected 
into two fascicles. Each fascicle is furnished with a spine (fig. 4), 
with two forceps (fig. 5), and with many lanceolate bristles curved 
at the points (fig. 6) and very sharp, with a double edge at the 
point of curvature. I have not before met with a worm furnished 
with forceps-like bristles; and none of the kind are figured by 
Audowin and Edwards. 
The worm lives in a tube which has a singularly exact resem- 
