378 
THE VOYAGE OF H.M.S. CHALLENGER. 
ventral muscles are lateral in position, passing from the dorsal angle to the nerve-trunk 
on each side. 
The ventral wall is formed by the circular coat formerly mentioned, and a thin 
lining of longitudinal fibres. This slender region is, hovrever, supported externally by 
the massive w'hite hypoderm. 
The meshes above the ventral wall contain large clear yellowish masses resembling oil. 
Within the longitudinal layer of the alimentary sheath is a thin circular coat. The 
whole thickness of the wall of the canal is occupied by w’ell-marked granular glands, 
with the exception of the limiting membrane internally and the thin boundary 
externally. Interiorly the sheath gives off a loop to the ventral wall enclosing the clear 
yellowish snbstance and sujaeriorly a vessel. 
In the posterior region the body is less flattened. The ventral hypoderm, though still 
forming a dense layer, is considerably thinner than in front. The rounded nerve-cords 
have moved inward, and occupy the angle on each side of the median depression. The 
ventral longitudinal muscles are proportionally larger than in front, and have followed 
the nerve-cords inward, a median band of longitudinal fibres forming an isthmus 
between them. The large alimentary tract occupies most of the body-cavity. 
When a transverse section of a tentacle is made the wall of the organ is formed of 
external circular and internal longitudinal fibres, the whole invested by a layer of hypo- 
derm with only a definite boundary-line to represent cuticle. The inner surface of this 
hypoderm is greatly thickened, and contains reddish-browm pigment and peculiar 
granular bodies. The pigment occurs in the median fold and adjoining grooves. This 
region is evidently the active portion of the organ, as in the tentacles of various 
members of the Spionidae, such as Polydora. The general structure of the ap- 
pendage corresponded wfith that shown by Claparede in Telepsaviis costarum} 
Examples of Phyllochcetopterus are not uncommon in the Mediterranean, and at least 
one of the sjDecies extends to Madeira.^ 
Ranzania, Claparede. 
Ranzania (?) eapensis, n. sp. (PI. XXIIIa. figs. 19, 20). 
Habitat. — Dredged at Station 141 (Cape of Good Hope), December 17, 1873 ;lat. 
34° 41' S., long. 18° 36' E.; depth, 98 fathoms; bottom temperature 49°‘5, surface 
temperature 65°'5 ; sea-bottom, green sand. 
This species inhabits a small tube composed of secretion coated with Globigerince, sand- 
grains, and minute particles of various kinds. None of the fragments exceed 20 mm. in 
' Anuelides sedentaires, p. 23, pi. xiii. fig. 9. 
2 Langerliaris, Nova Acta Acad. Cms. Leap., Bd. xlii. No. 3, p. 114. 
