24 
THE VOYAGE OF H.M.S. CHALLENGER. 
canal is capacious, its first division being largely dilated and covered by transverse rugae. 
A powerful layer of longitudinal muscular fibres is developed externally at the posterior 
part of the proboscis. 
The central organ of the nervous system occurs in the caruncular region, a little in 
front of the median tentacle, in the form of a bilobed mass. It is interesting that the 
separate nerve-cords in front are smaller in proportion than the trunks after they form 
the double cord. The nervous system on the whole is feebly develoj^ed. 
On each side, in a line with the median tentacle, is a large ocular (?) organ, which 
appears to be single. Section, however, shows that there are two deep centres of the 
pigment, and that there is a tendency to facets on the surface. Each mass forms a pro- 
minent oval projection, and appears minutely dotted under a lens. 
On the dorsum of the second body-segment are a number of prominent warty rugae 
of the hypoderm. 
Two small specimens from the Atlantic, named by Prof. Grube Amphinome vagans, 
differ in no respect from the foregoing. They came from the Godeffroy Museum. This 
species is probably the Amphinome pallasii of De Quatrefages,^ from the Azores and the 
Antilles, and is certainly the Pleione tetraeda of M. -Edwards.^ 
Ilermodice, Kinberg. 
Hermodice carunculata, Pallas (PL V. ; PI. IIIa. figs. 1-4). 
He7'modice carunculata, Auctorum. It is doubtful -whether Seba’s Millepod amarina amhoinensis, 
Seba, Tbes. Ser. Nat., i., tab. Ixxxviii. p. 131, be the same. 
Habitat . — A large specimen measuring upw'ards of a foot in length was procured at 
the surface of the bea near the Bermudas, while a bleached example about a fourth the 
length comes from the littoral region of the same islands. Two others were found 
at St. Vincent, Cape Verde Islands, in July 1873 ; and two were collected at St. 
Thomas, West Indies, in March of the same year. 
In those best preserved the characteristic features are the dull greenish or slate-bluish 
finely corrugated dorsum, the small size of the branchial tufts as compared with Amphi- 
nome rostrata, the pale buff of the ventral surface, and the alternation of the dorsal processes. 
The body is even more distinctly tetragonal than in Amphinome rostrata, this 
character being heightened by the issue of the bristles from the prominent angles. 
The diminution of the body posteriorly is well marked. The segments are clearly 
defined, and range from sixty-seven to seventy, and in the large example to one hundred 
and fifty-five. On the ventral surface a large vessel runs along the median line and is 
visible externally. The anus opens' as a somewhat symmetrically corrugated orifice on 
the dorsum, and there is a peculiar papilla, projecting posteriorly at the lower border. 
1 Anneles, i. p. 394. Efegne Anini. ill., pi. viii. his, fig. 1. 
