452 
THE VOYAGE OF H.M.S. CHALLENGEE. 
Pistafasciata, (Grube?) (PL XLIX. fig. 5 ; PI. XXVIIa. fig. 28 ; PI. XXXVIIIa. fig. 3). 
Terebella {Pliyzelia) fasciata, Grube, Mouatsber. d. k. preuss. Akad. d. Wiss. Berlin, Jabrg. 
1869, p. 513. 
Habitat. — Dredged off Kobe, Japan, in 8 to 50 fathoms. 
The specimen is incomplete, but it is of considerable size, measuring 35 mm. in 
length, and having a diameter anteriorly of 3 '5 mm. 
In the general form of the body it agrees, even in minute detail, with Pista 
cristata. The bristles, however, are much more tapered at the tip, and the Avings are 
narrower, the whole organ being less robust. 
The hooks (PI. XXVIIa. fig. 28) have the same relative proportions of the crown and 
the great fang as in Pista cristata, but the space beneath the latter is much less. There 
are also other differences in regard to the curve above the anterior inferior jDrojection, 
the structure of the spinous process above the latter, and the outline of the basal region. 
These minor distinctions, though noteworthy, cannot be said to be great. 
The branchim appear to have finer branches than any European example of Pista 
cristata. There are two pairs, but each organ differs in size, the right posterior being 
the largest. 
The greyish mud in the intestine is rich in Diatoms, with here and there a sponge- 
spicule. 
The chief feature in transverse sections of the anterior third of the body is the 
enormous size of the oblique muscles (PI. XXXVIIIa. fig. 3), which pass from the 
supero-lateral region on each side to the ventral border, leaving between them a very 
wide hiatus. The cuticle and hypoderm are fairly developed, the latter having its 
maximum depth in the median ventral area. In this species the splitting of the strong 
circular coat at the nerve-area apparently in the interganglionic region is well seen. 
Moreover, the outer band of fibres receives considerable accessions from the oblique 
muscles, the fibres passing right through the inner fibres of the circular coat. The 
latter shows a raphe at the four points of connection with the oblique muscles. The 
arrangement of the oblique bands causes the longitudinal ventral muscles to be almost 
lateral in position. They are much more massive than the extended dorsal longitudinal 
muscles. A thin layer of longitudinal fibres is situated as usual inside the circular coat 
above the nerve-area. Large glandular organs occur in the perivisceral chamber, above 
the foregoing area, and in the spaces outside the oblique muscles. The oesophageal 
region of the alimentary canal has a thick circular coat below the outer (longitudinal), 
and the glandular lining is closely frilled. 
This species has been referred with some doubt to Grube’s form as interpreted by 
Marenzeller, but the anterior inferior border of the hook differs ; for the latter in 
