MAGHLONA ROSEA. 487 
also curved. The most powerful are those intermediate in position, especially in front, 
and they are continued to the segment in front of the terminal sucker. 
Hach foot in this region has dorsally a short branchia, a tuft of two or three proportion- 
ally long, slender capillary bristles with traces of wings, and the powerful ventral hook (Plate 
CI, fig. 10), which is boldly curved and sharp at the tip, swells out below into a stout shaft, 
and then diminishes a little toward the base. It is longitudinally striated internally and 
marked by transverse streaks, and, though hard, is brittle. A comparatively large species, 
measuring more than an inch in length—1} or 14 inches. Snout with the median 
process and lateral supports. The median forms a kind of keel for some distance backward, 
and showed in the preparation from Ireland little tendency to be bifid. When viewed antero- 
posteriorly the wings touch the crown of the ordinary hook on each side. The branchiz 
are large from the tenth backward, diminish toward the posterior third, and on the tail 
form short processes or papille. The caudal sucker has the usual gap superiorly, but 
is smoothly rounded throughout the rest of its border. Hach branchia has an afferent and 
an efferent vessel. 
From Ardfry, on oysters, October 9th, 1904. Ireland (Southern). 
MaGELONA ROSEA, Moore, 1907. 
Specific Characters —Prostomium and peristomium are coalesced to form the broad 
ovoid head (in spirit), with dorsal cephalic ridges tapering to acute poimts, which diverge 
anteriorly. Peristomium with prominent lateral lobes; tentacular cirri arising laterally 
with papille, which increase in length distally. Proboscis soft, bulbous, with parallel striz. 
Body slender, depressed, tapering and sub-quadrate anteriorly; body 40 mm. long; segments 
about ninety-five. Ninth bristled segment with tapering simple bristles. Pygidium 
small, oblique, with anus dorsal, covered by a broad, flat papilla, and posteriorly with 
a pair of small slender cirri. Colour translucent white, intestine buff or greenish-brown, 
pharynx salmon-pink. In sand at and below low water. Nearly ripe in August. 
SYNONYMS. 
1907. Magelona rosea, Moore. Proc. Acad. N.S. Philad., p. 201. 
1914. » Southern. Proc. Roy. Irish Acad., vol. xxxi, No. 47, p. 105, pl. xvi, fig. 24. 
1920. _ , Hliason. Polych. Oresund, p. 52. 
1922. < » McIntosh. Ann. Nat. Hist., ser. 9, vol. ix, p. 23. 
Habitat.—Dredged in 7 fathoms in Killary Harbour, in mud (Southern).* 
Distribution.—Wood’s Hole, Mass. (Percy Moore), Swedish waters (Hlason). 
The larvee have been described by Fewkes as Prionospio tenuis, from Newport, and 
by Andrews, from Beaufort, N.C., and Wood’s Hole. 
1 Unfortunately the specimen sent by Mr. Southern had no ninth segment. 
