43 Canadian Arctic Expedition, 1918-18 
median lobe of the prostomium is small, the lateral ones are well.devel- 
oped, but not markedly dilated and not folded at ‘their anterior ends; 
neuropodia are clearly visible in each chaetiferous segment, those of the 
posterior branchial segments are long dorso-ventrally and almost reach 
the mid-ventral line; six pairs of nephridia, which open on the fourth 
to the ninth segments; one pair of conical oesophageal glands; a pair 
of small septal pouches; a pair of statocysts, opening to the exterior, 
and each containing numerous statoliths composed of sand: grains.” 
The specimen from Bernard harbour affords a welcome opportunity of 
checking most of the characters given in this diagnosis. The worm is 75 mm. 
in length, but the hind-body or ‘“‘tail’’ is obviously incomplete, being represented 
| 
A. glacialis, anterior portion, dorsal aspect. x4. N), first notopodium. 
by a portion only 4mm. in length exhibiting about seven annuli and a torn 
posterior surface. There are seventeen chaetiferous segments, the last eleven 
of which bear gills, which, however, are badly preserved, most of the gill-fila- 
ments having disappeared. Of the few gills which remain one—the right one 
on the fifteenth chaetiferous segment—was removed for examination. It consists 
of a short basal lamina from the distal margin of which ten axes are given off. 
These divide for the most part dichotomously and the resultant filaments— 
eleven in number on the longest-axis—are elongate, but their elongation is almost 
certainly due in part to maceration. The length of the longest axis from its 
base to the tip of the terminal filament is 5mm., while in the type specimens 
the longest axis is not more than 2 mm. in length. : 
The prostomium is fully exposed and corresponds exactly in the proportions 
of its parts with the published figures. 
The annulation agrees with that shown in the accompanying diagram, 
which was drawn from one of the types. : 
