POLYCELETA—BENHAM. 
63 
The dorsal ramus of tlie foot (fig. 66) is rather shorter than the ventral, and the 
two diverge at an angle which approaches 90°. Indeed, in less well-preserved specimens, 
this angle is a right angle. The end of each ramus is bluntly pointed and appears brown, 
especially in those cases in which the membrane has been torn away. The “ pinnal 
membrane ” is characteristically developed, and resembles that of T. nisseni Rosa. 
On the dorsal surface it commences on the base of the foot, some distance proximad of 
the bifurcation; its line of origin is undulating, as also is its margin. The membrane 
continues round the apex, and only ceases at the angle formed by the two rami. The 
arrangement of the ventral pinnal membrane is similar, but it is more extensive. It 
bears two “ pinnal glands,” which are termed by Rosa the “ hyaline ” and the 
“ chromophil ” glands.* There is no “ rosette.’' The species, therefore, belongs to 
Rosa’s sub-genus Tomoptens. 
The “ hyaline ” gland is capped by a dark orange or red brown mass of pigment, 
and is situated just dorsal of the apex of the ventral ramus. It makes its first 
appearance on the 3rd foot. 
The “ chromophil ” gland (the “ cupule ” of Quatrefages) appears as a rounded 
glandular thickening, differing in texture, as in its pale buff colour, from the surrounding 
transparent membrane. These glands commence on the 5th foot, and are recognisable 
as far back as the 20th, beyond which I am unable to detect them. 
’Idle two larger specimens are males, and the young testis is situated in the dorsal 
lobe of the foot, along the roof of its cavity. 
Locality .—- 
Commonwealth Bay. Pack ice. 
Distribution. —-Antarctic Ocean, lat. 60° 3' South, long. 0° 60' (Quat.). Between 
Kerguelen and Macdonald Islands (McIntosh). 
Remarks. —This species formed the basis of Quatrefages’ account of the genus 
in his “ Histoire Naturelle des Anneles,” and his account has been repeated, 
though recast, by Rosa (1908, p. 312) in his useful monograph of the genus. 
Quatrefages’ specimen had been collected during the voyage to the South 
Polar Regions of the Zelee (1837-1840), though it is not mentioned in the 
reports of that voyage. The specimen was imperfect, lacking the hinder end 
and the long cirri. It is described as being opaque and “ maroon coloured ” 
(which agrees probably with the present specimens). Owing to the imper¬ 
fections of the type, I have deemed it worth while to enter pretty fully into 
detail, for the species lias not been examined or reported upon since 1865. 
Quatrefages, in his figure of the head ” (pi. XX, fig. 1) shows the epaulettes 
as triangular, and, as I have mentioned, it is so when the animal is ill preserved. 
The foot (Quat., fig. 2) is possibly somewhat distorted, as the angle made by 
the two rami is greater than it is in well-preserved material. Here, again, I 
*Though the gland takes hsematoxylin very strongly, it is not noticeably affected by alum carmine, which I used. 
