Clare Inland Survey — Arehiannelida and Poly chaeta. 47 105 



Magelona papillicornis Fr. Miiller. 



1896. Mesnil, p. 257. 



Frequently obtained in Blacksod Bay by digging in sand near low-water 

 mark. 



Habitat. — Blacksod Bay — Common in clean sand near low-water mark. 



Clew Bay— Dredged in 5|-11 fins., on a sandy bottom. 

 Distribution. — British Isles ; shores of Europe ; Mediterranean. 



Magelona rosea Moore. 



1907. Magelona rosea. Moore, p. 201. 



Only one species of Magelona has been previously recorded from European 

 shores. This species has been referred by all zoologists to the M.joapitticornis 

 found by Fritz Miiller on the coast of Brazil. As Moore (1907, p. 204) has 

 pointed out, the two forms are probably specifically distinct. The form 

 which occurs at Wood's Hole, Massachusetts, was examined by Moore, and 

 found to differ markedly from the European M. •papillicornis. Whether the 

 latter species occurs on the American coast is still uncertain. 



The most striking difference between M. rosea and M. ■papillicornis lies in 

 the structure of the setae of the ninth setigerous segment. In the former 

 species these setae are finely tapered to a point ; in the latter they terminate 

 in a characteristic bulbous tip. A number of specimens dredged from the 

 muddy bottom of Killary Harbour agree with M. rosea in the structure of the 

 setae. I sent several of the specimens to Professor Moore, and he confirmed 

 the identification. This species also occurs in Galway Bay. The difference 

 in habitat of the two forms in Ireland is very striking, 31. papillicornis being 

 found in clean sand, M. rosea in mud. 



Habitat. — Dredged in 7 fms. in Killary Harbour, on mud. 



Distribution. — Wood's Hole, Massachusetts. 



Family DISOMIDAE. 

 Poecilochaetus serpens Allen. 



1904. Poecilochaekis serpens. Allen, p. 79. 



The larval form of this species has been described by Claparede, Levinsen, 

 Mcintosh, and Gravelly. It is very commonly taken in the tow-net during the 

 summer and autumn months. The adult has up to the present only been 

 recorded by Allen, who obtained it by digging in sand at low-water spring- 

 tides. Last year I found a number of adults in sand on the shore of Lough 

 Swilly. I have no doubt that the specimens obtained in the tow-net are the 

 larval forms of this species. The setae in the later larval stages are very 



R. I. A. PEOC, VOL. XXXI. O 47 



