Clare Island Survey — Archiannelida and Poh/chaeta. 47 127 



Polycirrus caliendrum Claparede. 



1894. Polycirrus caliendrum. De Saint- Joseph, p. 237. 



Numerous specimens of this species were found throughout the area. It 

 was most commonly found in Laminaria roots; but it was also found in the 

 sand of a Zostera bed, and was dredged on several occasions. Mature 

 specimens were found in March and May. 



The species most commonly recorded from the European coasts is P. auran- 

 tiacus Grube. It differs from the present species in having only three pairs 

 of nephridia instead of six pairs. In other respects the two species are 

 almost identical. A careful examination of all the Irish specimens has shown 

 that in all cases six pairs of nephridia are present. The three posterior pairs 

 are, however, very small and easily overlooked. The three anterior pairs are 

 large and easily seen lying free in the body-cavity, whilst the three posterior 

 pairs are hidden by overlying transverse strands of muscle. 



In view of these observations, it seems probable that a large proportion 

 of the records of P. aurantiacus should really be referred to P. caliendrum, if 

 indeed the two species are not identical. I am not in a position to pronounce 

 definitely on this point. Specimens from various parts of Europe should be 

 examined and compared. 



Habitat. — Blacksod Bay — Found on 2 occasions, on the shore. Clew 

 Bay— Dredged on 4 occasions, in 7-16 fms. Ballynakill 

 Harbour — Dredged on 2 occasions, in 1-8 fms. Bofin 

 Island — Dredged in 16 fms. 



Distribution. — England ; France ; Naples. 



Polycirrus Smitti (Malmgren). 



1865. Ereutho Smitti. Malmgren, p. 391. 



This species was found by digging in clean sand and in muddy gravel in 

 Blacksod Bay. Mature specimens were found in May. 



The capillary setae occur on 13 segments. They are very slender, and 

 either without, or with only a slight indication of, wings. The edge of the 

 seta is sometimes serrate ; but this is owing to abrasion, and is not a specific 

 character. The uncini have a single row of small teeth on the crest of the 

 large tooth. The base of the uncini is striated. There are six pairs of 

 nephridia. 



Habitat. —Blacksod Bay — Obtained on the shore on 3 occasions, by 

 digging in sand and muddy gravel. 



Distribution. — Scotland; Arctic shores; Scandinavia; Eastport, Maine, 

 U.S.A. 



