324 PRAXILLELLA GRACILIS. 



2. Peaxillblla gracilis, Sars, 1861. Plate CI, figs. 5 and 5 a— head and tail ; Plate CIX, 



figs. 12 and 12 a — bristle and hook. 



Specific Characters. — The anterior border of the head produced into a filiform 

 process projecting from the conical base. The margin of the cephalic plate, which slopes 

 somewhat more obliquely downward and forward than in P. prmtermissa, extended into a 

 broad flap, especially antero-laterally. The narrow median keel stretches far backward; 

 the nuchal organs are long, the anterior end bending outward. The papillse of the 

 proboscis are conical, large, and there are nine to ten in each row. Body is constricted 

 anteriorly, rounded dorsally, slightly flattened and grooved ventrally; nineteen bristled 

 segments, and four without bristles posteriorly. Anal funnel with a long ventral cirrus 

 and about twenty-five small cirri. Segmental organs in bristled segments 6 to 9. 



Bristles of two kinds — strong bristles having straight shafts and slightly curved tips 

 with narrow wings, and more slender translucent forms with just a trace of wings. 



The hooks have rather long, curved shafts with a distinct shoulder, somewhat short 

 neck, which increases in breadth distally, the main fang coming off nearly at a right angle 

 with the gular bristles close to its base, and five or six teeth on the crown behind it. 



Somewhat soft tube of mud and sand lined by a translucent amorphous secretion. 



Synonyms. 



1856.? Clymene quadrilobata, Sars. Fauna Lit. Norv., ii, p. 5, Tab. 2, figs. 18 — 22. 

 1861. „ gracilis, idem. Christ. Vid.-Selsk. Forh., p. 91 (sep. copy), p. 22. 



Sars. Nyt Mag. f . Naturvid., xi, p. 256. 

 De Quatrefages. Annel., t. ii, p. 657. 

 Malmgren. Nord. Hafs- Annul, p. 192. 

 idem. Annul. Polych., p. 100, Tab. xi, fig. 63. 

 Mcintosh. Trans. Roy. Soc. Edinb., vol. xxv, p. 421. 

 Ehlers. Zeitschr. f. wiss. Zool., Bd. xxv, p. 26. 

 Tauber. Annul. Danica, p. 125. 



Verrill. Trans. Conn. Acad. Arts Sc, vol. iv, p. 298. 

 Levinsen. Vidensk. Meddel. Nat. For., p. 144. 

 Bidenkap. Christ. Vid.-Selsk. Forh., p. 114. 

 Verrill. Trans. Conn. Acad. Arts Sc, vol. x, p. 665. 



Marenzeller. Denkschr. Math. Nat. CI. k. Acad. wiss. Wien, Bd. 74, p. 21. 

 Arwidsson. Skand. u. arktisch. Maldan., p. 183, Taf. iv, figs. 153—155, 

 Taf. v, figs. 156—158, Taf. ix, figs. 302—307, Taf. xii, fig. 367. 

 Augener. Westind. Polych., p. 162. 



Percy Moore. Proc. U. S. Nat. Mus., vol. xxxvii, p. 142. 

 Mcintosh. Ann. Nat. Hist., ser. 8, vol. xi, pp. 100, 115, 119, 124. 

 „ „ ,, var. borealis, Nolte. Wiss. Meeresuntersuch., n.f., Bd. xv, p. 38, Taf. i, figs. 12, 



13, Taf. ii, fig. 32, text-fig. 11. 



Habitat. — Fragmentary small examples were dredged in 100 fathoms in St. Magnus 

 Bay, Shetland, 1867 (J. G. Jeffreys). 



In the < Porcupine ' Expedition of 1870 it occurred in 81 fathoms off Cape Finisterre. 



ii 



ii 



1865. 



a 



>) 



Praxilla 



1867. 



a 



1869. 



a 



1875. 



a 



1879. 



a 



1882. 



Praxillella 



1883. 



Clymene 



1894. 



a 



1900. 



Encylmene 



1902. 



Clymene 



1906. 



Praxillella 



)> 



Praxilla 



1909. 

 1913. 



Praxillella 



