248 CIRBATTJLTTS OHIAJII. 



Synonyms. 



1828. Lumbricus filigerus, Delle Chiaje. Mem., iii, p. 178, tav. xlv. 



1840. Cirratulus LamarcMi, Grube. Actin. Echin. u. Wiirm., p. 70. 



1841. ,, filigerus, Delle Chiaje. Descrizione, iii, p. 85; v, p. 99, tav. xci, figs. 1 — 2, tav. Ixxx, 



% i. 



1868. Audouinia filigera, Claparede. Annel. Nap., p. 267, pi. xxiii, fig. 3. 

 1885. „ „ Cams. Fauna Medit., p. 247. 



1900. „ „ Ehlers. Schwed. Magellan. Annel., p. 14. 



1901. „ „ idem. Annel. Sammlung Plate, p. 265. 

 1911. „ „ Fauvel. Arch. Zool. exper., vol. xlvi, p. 410. 



„ „ filigerus, Mcintosh. Ann. Nat. Hist., ser. 8, vol. vii, p. 154. 



1914. ? Cirratulus norvegicus, Southern. Proc. Roy. Irish Acad., vol. xxxi, no. 47, p. 107, pi. xi, 



figs. 26, a— d. 



Habitat. — Malahide, Co. Dublin, Roy. Irish Acad. ; various parts of the Irish coast 

 (Southern). 



If this is the Audouinia filigera of Claparede and Delle Chiaje it occurs at Algiers 

 (Marion) ; Marseilles (Marion and Bobretzky) ; Naples (Delle Chiaje and Claparede) ; 

 Gulf of Persia (Fauvel) ; Magellan (Ehlers). 



The head forms a short cone, the mouth opening on the buccal segment a little behind. 



The body is more slender and delicate than in G. tentamlatus, proportioually more 

 elongate, and but slightly tapered anteriorly and posteriorly, the anus being dorsal with a 

 short terminal cone beneath it. The first three segments, that is, the buccal and two 

 following, are acha3tous, and the first bristled segment is hardly wider than that in front. 

 It bears a dorsal and a ventral tuft of capillary bristles of moderate length, and the suc- 

 ceeding seventeen or eighteen are similar in this respect. At the twentieth foot the dorsal 

 division has three slender, curved crotchets, and about the same number of somewhat 

 flattened capillary bristles, with finely tapered tips, and alternating with the crotchets ; 

 ventrally are three much stronger curved crotchets with a few short and slender capillary 

 bristles, the proportions of these being seen in the sketch (Plate XCIV, fig. 18). 



Immediately behind and rather above the first bristle-tuft is a branchia, and so with 

 the three following feet. On the dorsum in the line between the fourth and fifth bristle- 

 tufts is a group of slender branchiae, apparently four or five on each side. In the pre- 

 paration they are shorter than those which follow in single series on each side along 

 the dorsum, and they occur sparsely distributed along the posterior region till near the tail. 



This form differs from G. tentamlatus in so far as the crotchets appear in the ventral 

 division about the twentieth bristled foot, and in the dorsal division shortly after the 

 fortieth. The hooks (Plate CVII, fig. 3) have their curves somewhat more pronounced 

 than in G. tentamlatus, and posteriorly the ventral are larger and stronger than the dorsal. 

 Both are accompanied by a few capillary bristles. 



This may be the Audouinia filigera of Claparede. He describes a single pair of 

 segmental organs in the first setigerous segment, their apertures on the ventral surface 

 being marked by pigment. 



Cams (1885) observes that it resembles Audouinia LamarcMi, of which it may be a 

 variety, but that the tentacular filaments occur on the fifth, not on the seventh, body-segment. 



