276 DASYCHONE ARGUS. 
Herm and Guernsey ; between tide-marks, Lamlash, Arran (Dr. Howden) ; thirty fathoms 
off Bantry Bay, 8.W. Ireland, Royal Irish Academy’s Expedition, 1885, where the species 
seems to be abundant, groups of three or more being fixed to the surface of littoral sponges. 
Plymouth (Spence Bate and B. Rowe). Bay of Galway (H. P. Wright). Between tide- 
marks, Malahide, Co. Dublin (A. C. Haddon); Dublin Bay and West Coast of Ireland 
(Southern). A common form in the older collections of Cocks, Leach and others from the 
southern coasts and now in the British Museum. Cosmopolitan. Shores of France (fauvel), 
Spitzbergen (Meyer), Norway, Sweden, Heligoland (Malmgren); Teneriffe (De Quatrefages) ; 
Finmark (Norman). Coast of France, Dinard (De St. Joseph) ; Shores of Cantabria (Rioja) ; 
Mediterranean, Adriatic, Sargasso Sea (Grube); Antarctic Seas (Ehlers). 
When the branchize have been shed, the edge of the collar projects beyond the surface 
of the cephalic plate (Plate CX XI, figs. 2 and 2a), which shows at the dorsal inflection two 
small processes or folds from which a pear-shaped area passes ventrally to end in the oral 
ridge. The entire surface is thus symmetrically mapped out, whilst the margin is formed 
by the collar, which presents a lateral notch—in the form either of a slit or a shallow excava- 
tion—marking off the reflected and somewhat triangular ventral lobes from the rest of the 
brim, whilst they are separated from each other by a wider gap in the mid-ventral line (Plate | 
CXX, fig. 14a). In large examples a dark speck occurs on each side of the surface external 
to the pear-shaped enlargement, and another on each side of the dorsal collar. A patch of 
dark brown pigment also is present in some on the edge of each reflected lobe. When the 
annelid withdraws itself into its tube, the dorsal lamellee are folded inward and slightly overlap, 
and the inner process is pressed flat. 
The branchie (Plate CXXI, figs. 1 and la) arise from firm chordoid tissue which is 
continuous in each semicircle, and apparently formed by the fusion of the bases of the branchie, 
the individual elements being marked by a reddish-brown pigment-speck, linear in outline 
and interfilamentar in position. From each semicircle the finely coloured organs freely 
extend distally. The chordoid axis in each is more finely divided than in Chone infundibu- 
liformis. The pinnee, which are in a double row, become shorter at the tip and somewhat 
suddenly cease at the base of the short terminal process. Along the outer edge of each 
filament about eighteen clavate processes are attached in pairs (Plate CXXI, figs. 1 and 1a), 
and a pigment spot occurs on each side just beyond the point of attachment. The processes 
in life are often carried downward. Sars calculated that there were from 1200 to 1400 eyes 
in this species, for each eye-speck is compound. As a transparent object, the branchial filament 
shows the chordoid axis (a, Plate CXXI, fig. 1c) with its coating of hypoderm and cuticle, 
and the pinnee present also jointed chordoid axes.' In some from Guernsey and one from 
Plymouth (Plate CXIIIA, fig. 5) the branchiz were of a pale greenish hue, whilst the pinne 
were pale or whitish, and the tentacles greenish. Zetlandic examples, again, had the branchice 
tinted dull orange with a tinge of green, whilst on each filament the pinne and the dorsal 
processes were marked with white grains. Others from St. Peter Port, Guernsey, had dull 
purplish red branchiz spotted with white. Four of the dorsal crenated processes in some 
were also white. In those from St. Andrews the branchize are often brownish purple, and 
the two tentacular processes are streaked longitudinally with white and purplish brown. 
The beautiful shades of white and purplish brown and the elegant form of these complicated 
1 De St. Joseph calls the axis cartilaginous. 
