156 NICOLEA VBNUSTULA. 



lateral view above the main fang, and pressure occasionally causes the second to project, 

 whilst others in the same position show two teeth above the main fang — even in the same 

 row with those having only the main fang and a single tooth above it. In one male most 

 of the hooks showed this third tooth, but it does not appear to be a sexual character. 

 Many examples of the species (N. venustula) show a single tooth above the main fang 

 in front, and two in the posterior hooks. 



Malmgren distinguished what appears to be a variety of the foregoing as Nicolea 

 arctica from Spitzbergen and Greenland, but so far as recent examinations go it seems to 

 be unnecessary to give it specific distinction, and this is also the view of Levinsen and 

 Marenzeller, though Wiren follows Malmgren. In this variety the structure of the collar 

 agrees with, N. venustula. The body has from forty to seventy segments, with about 

 fourteen ventral shields, the last three being rudimentary. 



The colour of the male variety (N. zostericola) is whitish, of the female reddish with 

 a white lateral line. Branchise two, apparently with finer branches than in N. venustula * 

 and more widely spread. The setigerous processes number fifteen pairs, the bristles in 

 two groups with golden shafts, short, tapered tips with narrow wings. The hooks have 

 two teeth above the great fang (Plate CXXVI, figs. 4 and 4 a). The tube is composed 

 of mud. This variety was dredged in deep water off Shetland and at Station 8 to the 

 west of Ireland in the " Porcupine " Expedition of 1869. It is probable that the Terebella 

 long icor tils of M. Sars 1 (1829) is a Nicolea. 



Hessle (1917) found most of those on the Scandinavian coast had fifteen pairs of 

 bristles. 



In the British Museum, prep. 62 . 7 . 12 . 47 from Polperro, labelled " Terebella con- 

 strictor," appears to be Nicolea venustula. 



A variety of this widely distributed form was procured by the " Knight Errant " in 

 the trawl at 640 fathoms at Station 8, 22nd August, 1880, and it was from certain 

 peculiarities considered at first to belong to a different type. Further examination, 

 however, demonstrates that it may more fitly be placed as a marked variety of Nicolea 

 venustula, Montagu. It was originally described as Melinella Macduffi. 2 The cephalic 

 lobe agrees with that in the genus, and ventrally the buccal segment forms a rim behind 

 the mouth. Ten glandular scutes occur anteriorly on the ventral surface instead of 

 thirteen in the ordinary form and the ten anal papillae are longer than usual. There 

 are eighteen pairs of bristles anteriorly instead of the ordinary seventeen. Two branchiae 

 only occur on the first segment as two slightly branched organs supported on pedicles. 

 The tip is dichotomously divided in some parts, whilst in others it is irregular. Not 

 more than a dozen filaments occur in each branchia. The setigerous processes, which 

 commence on the third segment, are minute and appear to be about eighteen in number. 

 Each bears a small tuft of translucent bristles with delicately tapered slightly carved 

 tips with narrow wings (Plate CXXV, fig. 4) and arranged in two series, a longer and a 

 shorter, the shorter, however, being only a little within the tips of the longer. 



3 'Bidrag. Soedyrenes Naturhistorie/ p. 28, Tab. i, figs. 7—9, Bergen, 1829. This is a note- 

 worthy production for a theological candidate. 



2 < Ann. Nat. Hist./ ser. 8, vol. xiii, p. 109, 1914. 



